In biological classification, a subfamily (Latin: subfamilia, plural subfamiliae) is an auxiliary (intermediate) taxonomic rank, next below family but more inclusive than genus. Standard nomenclature rules end botanical subfamily names with "-oideae", and zoological subfamily names with "-inae".
Detarioideae is an example of a botanical subfamily. Detarioideae is a subdivision of the family Fabaceae (legumes), containing 84 genera.
Stevardiinae is an example of a zoological subfamily. Stevardiinae is a large subdivision of the family Characidae, a diverse clade of freshwater fish.