The moss project seeks to find and remove the furry green typos that have been growing on Wikipedia articles. It uses a python script named moss and written by User:Beland to automatically find misspellings, mistakes in English grammar, violations of the Wikipedia:Manual of Style, and confusing or broken wiki markup.

Death to typos!

QUICK LINK TO THE BEST PAGE FOR NEW PARTICIPANTS

About misspellings[edit]

How the lists are made

The moss spell checker is run against a recent set of database dumps, which are generated on the 1st and 20th of every month (but take a few days to process). All the articles in the English Wikipedia are examined. The following are ignored:

Many mistakes are not (yet) caught:

2023 statistics

See also: Older statistics
Dump (moss version) Parse failures (articles + articles with MOS:STRAIGHT violations) TOTAL (instances) A BC BW C D H HB HL L ME N P T/ T1 TE TF TS U Z
2023-01-01 (c2370a5) 161163 + 29891 1187870 10615 83981 534264 8233 0 1498 4601 110 1975 179206 1905 5 2229 41525 6115 198814 97810 1428 13556
2023-01-20 (36ce94e) 161298 + 29949 1182833 10598 83813 534411 8235 0 1525 4965 116 1958 178578 1889 6 2196 38722 6055 198441 96321 1402 13602
2023-02-01 (90a97fc) 161048 + 29944 1180485 10602 83842 534121 8245 0 1500 5011 111 1936 178163 1862 6 2183 38247 6050 197047 96542 1392 13625
2023-02-20 (f606b45) 161111 + 30009 1180176 10609 83664 534782 8249 0 1509 5224 108 1930 177709 1861 4 2071 37810 5997 196478 97105 1383 13683
2023-03-01 (75cbca7) 161224 + 30095 1179378 10613 83570 534792 8206 0 1510 5286 100 1918 177568 1860 5 2076 37445 5970 196360 97010 1382 13707
2023-03-20 (56a3811) 161344 + 30169 1177045 10566 83245 535523 8214 0 1509 5202 99 1911 176955 1861 5 2092 36281 5811 196309 96321 1361 13780
2023-04-01 (no run)
2023-04-20 (57a4619) 161810 + 30162 1178156 10577 83076 536215 8241 0 1541 5473 105 1904 175853 2043 5 2049 36561 5740 196528 96979 1370 13896
2023-05-01 (77de75d) 162001 + 30150 1171871 10418 82887 536140 8170 0 1535 4633 98 1890 173066 2028 5 2050 36282 5781 195082 96960 1361 13485
2023-05-20 (73bb66d) 162329 + 30138 1171817 10379 82480 536386 8161 0 1470 4913 88 1890 171905 2037 0 2064 36364 5817 195132 97814 1367 13550
2023-05-20 (d0a8560) 163084 + 29893 1170266 10186 81955 529811 8192 0 1473 4902 89 1879 173759 2042 1 2064 38044 5842 194194 100920 1366 13547
2023-06-01 (040dd4d) 163371 + 29818 1169150 10189 81451 529652 8200 0 1474 5163 90 1895 172815 2031 1 2052 37997 5827 193963 101375 1365 13610
2023-06-20 (50a82ce) 163664 + 29771 1169732 10189 81086 529892 8232 0 1519 5624 86 1879 171891 2050 1 2059 38342 5785 194184 101817 1364 13732
2023-07-01 (8533535) 163877 + 29747 1169420 10201 80978 529664 8242 0 1564 5806 83 1873 171484 2042 3 2061 38446 5814 193933 102073 1373 13780
2023-07-20 (9812c05) 164115 + 29742 1170482 10174 80456 529875 8255 0 1553 5943 80 1872 171720 2036 3 2057 38956 5806 194057 102367 1361 13911
2023-08-01 (7468187) 164308 + 29748 1170928 10136 80230 529739 8249 0 1549 6036 79 1873 171743 2037 5 2061 39182 5811 194411 102497 1351 13939
2023-08-20 (7170d29) 164473 + 29635 1171932 10148 80137 529804 8263 0 1556 6132 80 1874 171627 2048 8 2062 39280 5856 194769 102930 1344 14014
Dump (moss version) Parse failures (articles + articles with MOS:STRAIGHT violations) TOTAL (instances) A BC BW C D H HB HL L ME N P T+gcld3_broken T/ T1 TS U Z
2023-09-01 (8c03bd1)* 164600 + 29593 1173119 10135 80154 530301 8245 0 1567 5692 87 1875 171823 2061 9 200991 2057 39595 103147 1337 14043
2023-09-20 (8c03bd1)* 164777 + 29611 1173098 10183 80123 530578 8240 0 1583 4775 85 1870 171711 2064 8 201138 2064 39874 103376 1339 14087
2023-10-01 (d531b95)* 164779 + 29586 1173193 10164 80017 530906 8238 0 1577 4719 87 1860 171300 2061 9 201083 2047 39886 103784 1328 14127
2023-10-20 (9c53721)* 164889 + 29667 1173548 10178 79977 531174 8243 138 1584 4762 87 1860 171070 2048 11 201277 2042 39910 103702 1323 14162
2023-11-01 (9c53721)* 165069 + 29668 1174710 10164 79988 531412 8252 138 1577 4738 90 1844 171440 2033 11 201449 2059 40250 103724 1338 14203
2023-11-20 (1edb851)* 165362 + 29748 1177078 10196 79995 531684 8262 138 1597 4859 93 1856 171957 2034 10 202060 2054 40847 103797 1323 14316
2023-12-01 (1edb851)* 165429 + 29788 1179043 10208 79941 531789 8294 138 1610 4950 93 1867 172253 2028 12 202513 2056 41284 104336 1310 14361
2023-12-20 (1edb851)* 165685 + 29862 1180181 10205 79762 531632 8362 138 1603 4895 103 1868 172415 2022 12 203189 2042 41499 104750 1301 14383

* Due to software issues, language detection wasn't working for this run.

2024 statistics

Dump (moss version) Parse failures (articles + articles with MOS:STRAIGHT violations) TOTAL (instances) A BC BW C D H HB HL L ME N P T+gcld3_broken T/ T1 TS U Z
2024-01-01 (1edb851)* 165792 + 29766 1180781 10226 79927 531362 8352 0 1628 4917 100 1865 172474 2027 9 203478 2043 41749 104903 1301 14420
2024-01-20 (2caa23a)* 165661 + 29837 1180491 10237 79493 531501 8345 0 1624 4127 103 1858 172622 2019 9 203838 2044 41878 105071 1298 14424
2024-02-01 (3242653)* 165836 + 29834 1181230 10245 79246 531803 8337 0 1629 4120 103 1858 172799 2024 8 204049 2043 42002 105240 1287 14437
2024-02-20 (10d0c37)* 165885 + 29901 1182750 10251 78915 531861 8343 1 1630 4043 114 1849 173461 2015 10 204251 2045 42357 105827 1286 14491
2024-03-01 (9ccfa0d)* 166045 + 29975 1182428 10255 78805 531778 8362 0 1638 4041 112 1854 173370 2030 24 203994 2037 42461 105848 1299 14520
2024-03-20 (460959f)* 166141 + 30055 1185611 10292 78621 532345 8424 0 1631 4237 116 1858 173672 2045 25 204545 2049 42870 106954 1278 14649

* Due to software issues, language detection wasn't working for this run.

Typo classification legend

Reporting symbol Explanation
Parse failure Mismatched punctuation; spell checker is unsure which words to ignore, so the whole page is skipped
A mAth
BC Bad Characters (not allowed by Manual of Style)
BW Bad Words (not allowed by Manual of Style)
C Chemistry words
D DNA sequence
H HTML/XML/SGML tag
HB Known bad HTML tag, like <font>
HL Bad HTML-like linking, like <http://...>
L Probable Romanization (transLiteration)
ME Probable coMpound, English (with and without dash) - need to be added to Wiktionary
N A-Z plus numbers and hyphens
P Patterns (e.g. rhyme schemes - Beland fixes these)
T/ Suspected MOS:SLASH violation
T1 Edit distance 1 from common English word
TE AI thinks it's trying to be English
TF AI thinks it's trying to be a non-English language (Foreign to English Wikipedia), sorted by language (e.g. TF+el)
TS Missing or extra whitespace or dash (or new compound). Currently included if there is a period (TS+DOT), comma (TS+COMMA), or extra space (TS+EXTRA). Missing bracket (TS+BRACKET) needs code improvements to be reliable, and the remainder of TS need sorting.
U URL
Z Decimal fraction missing leading Zero
I Definitely not English (International) due to accents or mixed with punctuation (other than hyphen)
MI Probable coMpound, non-English (International) in English Wiktionary (both A-Z and non-ASCII characters, with and without dash)
ML Probable coMpound, transLiteration
MW Probable coMpound, found in non-English Wiktionary
R Regular word (A-Z only) not near a common English word
T2 Edit distance 2 from common English word
T3 Edit distance 3 from common English word
W Not in English Wiktionary, in non-English Wiktionary

Instructions for editors

Just like a regular spell checker, sometimes a word that's highlighted is really a misspelling and should be changed, but sometimes it is a correct spelling that needs to be added to the spell checker's dictionary (which in this case is the English Wiktionary and Wikispecies). For the below lists, here's how you can help:

Don't worry if you miss something; it will reappear in a future report if there are still mistakes.

Suggested edit summaries

If you want to help publicize this project, you can copy-and-paste these into your edit summary, if appropriate.

For Wikipedia edits:

Fix misspelling found by [[Wikipedia:Typo Team/moss]] – you can help!
Tag non-English text found by [[Wikipedia:Typo Team/moss]] – you can help!
Tag correct text as ((not a typo)) for automated spell checkers (including [[Wikipedia:Typo Team/moss]])
Fix mismatched quote marks found by [[Wikipedia:Typo Team/moss]] – you can help!

For Wiktionary edits:

Add word identified by [[w:Wikipedia:Typo Team/moss]] – you can help!

Wiktionary cheat sheet

Need to add a word to Wiktionary? The Wiktionary cheat sheet has copy-and-paste templates that make it easy for the types of words commonly encountered here, even if you've never done it before.

Misspellings - lists of things to fix[edit]

Likely misspellings by article (main listing)

The most efficient list to work on if all you want to do is fix misspellings. These listings try to list all the typos from a given article, so they can be fixed all at once. It also tries to only show typos that legitimately need fixing. It's not perfect, so a few words found need to be added to Wiktionary or tagged as not English, not a typo, etc. Only a few letters are updated on each run, to avoid stale listings as the whole list takes far longer than two weeks to work through. (This also avoids duplicating recent work when listings are refreshed.)

See subpages due to length:

Notes:

Possible typos by length

(Updated from 2022-12-20 dump.)

Longest or shortest in certain categories are shown, sometimes just for fun and sometimes because they form a useful group. Feel free to delete articles that are fixed or tagged.

Likely chemistry words

These need to be checked by a chemist and marked as ((chem name)).

Chemical formulas

(Updated from 2023-05-20 dump.)

Chemical formulas should be written with HTML subscripts or ((chem2)); these listings identify those that incorrectly just use regular numbers.

Chemical formulas that use Unicode subscripts (which is against MOS:SUBSCRIPT) will be detected automatically by moss_entity_check.py.

Chemical formulas that use <sub>...</sub> are allowed by MOS:CHEM, but may show up in the main typo listings above. They can be converted to use ((chem2)) to be accepted by the spell checker, and ((chem2)) is also the way to fix listings of partial formulas.

Any "possible" listings that aren't chemical formulas can be cleared from this list by adding a redirect to an appropriate target (like Dy4 Systems). Most "known" listings that aren't chemical formulas can be fixed with ((proper name)).

Redirects added for strings that are chemical formulas should be added to Category:Chemical formulas.

Most chemical articles

Articles with a large number of chemical formulas triggering the spell checker are listed here (manual check on 2022-06-20 dump; counts include potential typos other than formulas, mostly compound names):

Possible chemical formulas that don't use subscripts

Note: These are easier to find by searching with "insource://", for example: insource:/Si6Al2/. -- Beland (talk) 02:32, 27 December 2022 (UTC)[reply]

Known chemical formulas that don't use subscripts

H2O
CO2
CS2

(Mostly not carbon disulfide.)

C2H2 zinc finger weirdness

These might be better written as Cys2His2; see Zinc finger#Classes. -- Beland (talk) 01:16, 18 June 2022 (UTC)[reply]

Remainder
Problem cases

Parsing problems (where noted) are probably resulting in words showing up in debug-spellcheck-ignored.txt that shouldn't. -- Beland (talk) 03:09, 27 December 2022 (UTC)[reply]

Repeating patterns

For rhyme schemes, they probably need to be re-styled to follow Wikipedia:WikiProject Poetry#Style for rhyme schemes. If this ends up making them all-caps, they won't show up here on the next run. For mixed-case rhyme scheme notations, use ((not a typo)) after making sure dashes, commas, and spaces follow the recommended style.

(All fixed as of 2022-12-20 dump!)

False positives

Is there a word that is correctly used in an article, but which shouldn't be added to Wiktionary? List it here, and Beland will fix the problem.

Archived solutions: Wikipedia:Typo Team/moss/Archive

False negatives

Is there a misspelled word in an article mentioned here that was not reported? Feel free to list it below and Beland will try to improve the code if appropriate.

These are currently over-ignored, but could be used to suggest correct spellings:

Archived notes

See Wikipedia:Typo Team/moss/Archive.

For Wiktionary[edit]

Spell-checking Wiktionary itself

A new project has started to do that using moss software, at wikt:Wiktionary:Spell check.

Triaged for Wiktionary

Dictionary writers needed! And speakers of languages other than English!

Many words (English and otherwise) detected as potential typos have been manually triaged as legitimate words that need to be added to Wiktionary, and are listed at Wikipedia:Typo Team/moss/For Wiktionary. (Moved from this page due to length.) Many of the subpages under the misspelling main listing also have long lists of words to add to Wiktionary, which are sometimes bundled up and moved to the "For Wiktionary" subpage.

Wiktionary aims to have definitions for all words in all languages (with some exceptions), and acts as the primary database for the moss spell-checker.

Highest-frequency words missing from dictionary (a-m)

(updated 2022-12-20) Good candidates for words to add to the English Wiktionary (which provides English definitions for words in all languages, including all compound words), as it seems English Wikipedia readers will frequently encounter them. For each run, only words from half of the alphabet are shown, to avoid duplicate work from when new dumps are being processed.

Most of the words are not from English. To get them off this list, you can either add an entry to the English Wiktionary (which provides English definitions for words in all languages) or tag all instances of the word on the English Wikipedia with ((lang)). Wiktionary does not accept Romanizations for some languages, so those cases must be tagged as ((transl)) or ((lang)).

Legitimate misspellings are candidates for Wikipedia:Lists of common misspellings. If there is an obvious correction, adding that to Wikipedia:Lists of common misspellings/For machines will help editors who use automated tools to fix cases faster.

Translation and general cleanup[edit]

See Wikipedia:Typo Team/moss/not English.

Mismatched markup and punctuation[edit]

Errors in punctuation (mostly quotation marks) and wiki markup generally cause confusion for readers, and also prevent the spell checker from running on these articles.

Inches and feet should not use " and ', per Wikipedia:Manual of Style/Dates and numbers#Specific units; use letters instead. (See MOS:UNITS for general guidance.) Where conversions are needed, use ((convert)), for example: 2 feet 3 inches (69 cm)


WORK IN PROGRESS

-- Beland (talk) 19:03, 4 September 2019 (UTC)[reply]

Gender-neutral language[edit]

Manned

The word "manned" and related forms like "unmanned" are used in many articles, but is not gender-neutral as required by MOS:S/HE and the NASA style guide. Gender-neutral alternatives include:

Not all instances need to be changed.

If the word is found the names of articles and categories (except those with names directly related to UAVs), those should be renamed, and the links changed. Many articles have already been renamed, and the links just need to be updated. (Remember that to rename a category, all the articles in that category must be edited to change their pointers.)

Borderline cases

These may need to be discussed before being changed.

Discussion in progress on Talk:Manned Venus flyby. -- Beland (talk) 09:37, 5 January 2022 (UTC)[reply]

Objections in specific cases:

Marriage

Wikipedia:Writing about women § Marriage points out:

Ladies

Wikipedia:Writing about women § Girls, ladies prefers "women" to "ladies" except where part of set phrases or traditional titles (like first lady). find all lowercase "ladies"

Instructional and presumptuous language[edit]

MOS:NOTE says to avoid the following phrases when they address the reader directly. Not all instances are problematic, such as those in direct quotations.

Internationally comprehensible spelling and vocabulary[edit]

MOS:COMMONALITY advises the use of vocabulary and spellings that are shared across national varieties of English, where possible. This section collects instances where an unshared term is being used which could be improved. For proper nouns and direct quotes, a translation or re-spelling into another dialect may be helpful.

looks like its wrapped up, with jail preferred except in proper nouns Xurizuri (talk) 15:36, 21 December 2020 (UTC)[reply]

Currency style[edit]

Per MOS:CURRENCY:

Find all problem cases for ₤

Caution: Not all problem pages show up reliably; if you do a search, fix all the pages in the results, and then do another search, you will probably get a fresh batch of problem pages. It may also take a minute or two for fixed pages to disappear from the results, due to lag updating the search index.

Work is in progress on detecting and fixing other MOS-related issues with numbers and currencies.

Small caps[edit]

Per MOS:SMALLCAPS, smallcaps are not to be used for years like "400 BC". Find all instances of known smallcaps issues...

HTML tags[edit]

Updated from 2024-04-01 dump.

You can do one of two things for these articles:

How to clean up

See Category:Articles with HTML markup for instructions on how to find the offending tags and what to do about them.

Find all articles by tag

Can't wait for the next database dump? Want to look for or fix all instances of a specific tag? Use the links below!

Additional HTML problems are listed at Special:LintErrors.


Sometimes editors use angle brackets (< and >) for other purposes. Though these are not HTML markup, they often need to be fixed.

<<...>> find all can indicate:

Other weirdness:

Known bad HTML tags (HB)

These are also included in the main listings.

Bad link formatting (HL)

These are also included in the main listings. Angle brackets are not used for external links (per Wikipedia:Manual of Style/Computing § Exposed URLs); "tags" like <https> and <www> are actually just bad link formatting. See Wikipedia:External links#How to link for external link syntax; use ((cite web)) for footnotes.

Unsorted (H)

Many of these can be replaced by ((var)) (for text to be replaced) or ((angbr)) (e.g. for linguistic notation). Enclose in <code>...</code> for inline software source code.

Need debugging

Notification of new dumps[edit]

"Most likely misspellings by articles" should always have work to do (if not, ping Beland to add more from the current dump). Some of the other sections are occasionally waiting for a new dump to get a useful list, either because they are ranked by frequency or a code change has been made to clean up noise in the next run. New runs are generally posted twice a month. The database snapshot from the first day of the month generally takes about 9-13 days to process, and the snapshot from the twentieth day of the month might take 4-6 days until it can be posted.

All that said, if you want to get a ping when results from a new dump are posted, you can add your name to the list below. If you are only interested in a particular section, include a note to that effect.

moss code and data sources[edit]

moss is written in Python, and is available on github at: https://github.com/cdbeland/moss

Data is obtained from XML database backup dumps.

  1. ^ "Phosphorus recovery from human urine and anaerobically treated wastewater through pH adjustment and chemical precipitation". Environmental technology. PMID 21879544.