The abbreviation viz. (or viz without a full stop) is short for the Latin videlicet, which itself is a contraction of the Latin phrase videre licet, meaning "it is permitted to see". It is used as a synonym for "namely", "that is to say", "to wit", "which is", or "as follows". It is typically used to introduce examples or further details to illustrate a point. For example: "all types of data viz. text, audio, video, pictures, graphics, can be transmitted through networking".
Viz. is shorthand for the adverb videlicet. It uses Tironian notes, a system of Latin shorthand. It comprises the first two letters, "vi", followed by the last two, "et", using the z-shaped Tironian "et", historically written ⁊[clarification needed],[note 1] a common contraction for "et" in Latin shorthand in Ancient Rome and medieval Europe.
In contrast to i.e. and e.g., viz. is used to indicate a detailed description of something stated before, and when it precedes a list of group members, it implies (near) completeness.
A similar expression is scilicet, from earlier scire licet, abbreviated as sc., which is Latin for "it is permitted to know." Sc. provides a parenthetic clarification, removes an ambiguity, or supplies a word omitted in preceding text, while viz. is usually used to elaborate or detail text which precedes it.
In legal usage, Scilicet appears abbreviated as ss. It can also appear as a section sign (§) in a caption, where it is used to provide a statement of venue, that is to say a location where an action is to take place.
Scilicet can be read as "namely," "to wit," or "that is to say," or pronounced // in English-speaking countries, or also anglicized as //.