 The specific military sense of a knight as a mounted warrior in the heavy cavalry emerges only in the Hundred Years' War.The verb "to knight" (to make someone a knight) appears around 1300; and, from the same time, the word "knighthood" shifted from "adolescence" to "rank or dignity of a knight".An Equestrian (Latin, from "eques" "horseman", from "equus" "horse") was a member of the second highest social class in the Roman Republic and early Roman Empire.