equine (adj.)

Proto-Indo-European root meaning "horse." Perhaps related to *ōku- "swift."

It forms all or part of: alfalfa; Eohippus; equestrian; equine; equus; hippo-; hippocampus; Hippocratic; Hippocrene; hippocrepian; hippodrome; hippogriff; Hippolytus; hippopotamus; Philip; philippic; Philippines; Xanthippe.

It is the hypothetical source of/evidence for its existence is provided by: Sanskrit açva-, Avestan aspa-, Greek hippos, Latin equus, Old Irish ech, Old Church Slavonic ehu-, Old English eoh, Gothic aihwa- all meaning "horse."

"unfair, unjust," 1660s, from in- (1) "not, opposite of" + equitable, which is ultimately from Latin aequus "even, just, equal." Related: Inequitably. The same formation in English has also meant "impassable on horses, unfit for riding over" (1620s), from Latin inequabilis, from equus "a horse" (see equine).

c. 1600, from Italian zebra, perhaps via Portuguese, earlier applied to a now-extinct wild ass, of uncertain origin, said to be Congolese [OED], or Amharic [Klein], but perhaps ultimately from Latin equiferus "wild horse," from equus "horse" (see equine) + ferus (see fierce). Related: Zebrine; zebroid.