Taxonomy was the part of biology dealing with the definition and classification of organisms. One taxonomic rank was the genus. (TNG: "The Chase", VOY: "Tattoo", "Distant Origin") Examples of taxonomic nomenclature, which were usually rendered in Latin include "Felis catus" (cats) (TNG: "Schisms") and "Homo sapiens" (Humans) (TOS: "Mirror, Mirror", "The Empath", Star Trek VI: The Undiscovered Country)
Data's poem Ode to Spot included the line "Felis catus is your taxonomic nomenclature". When a malfunction of USS Enterprise-D computer in 2369 caused the overwriting of several ship files with Data's personal files, the line about the taxonomic name of cats appeared on a PADD instead of the text of Something for Breakfast. (TNG: "Schisms", "A Fistful of Datas")
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