What is Knight?

Knight definition and meaning on Dictionary terms:
a mounted soldier serving under a feudal superior in the Middle Ages.
(in Europe in the Middle Ages) a man, usually of noble birth, who after an apprenticeship as page and squire was raised to honorable military rank and bound to chivalrous conduct.
any person of a rank similar to that of the medieval knight.
a man upon whom the nonhereditary dignity of knighthood is conferred by a sovereign because of personal merit or for services rendered to the country. In Great Britain he holds the rank next below that of a baronet, and the title Sir is prefixed to the Christian name, as in Sir John Smith.
a member of any order or association that designates its members as knights.

Chess. a piece shaped like a horse’s head, moved one square vertically and then two squares horizontally or one square horizontally and two squares vertically.
Nautical. a short vertical timber having on its head a sheave through which running rigging is rove. any other fitting or erection bearing such a sheave.

verb (used with object)
to dub or make (a man) a knight.