Rook

Rook (pronounced rook)

(1) A large Eurasian passerine bird, Corvus frugilegus, with a black plumage and a whitish base to its bill from the family Corvidae (crows) and noted for its gregarious habits.

(2) Slang term for a swindler at cards or dice

(3) To cheat, fleece or swindle.

(4) A bad deal; rip off.

(5) In chess, one of two pieces of the same color that may be moved any number of unobstructed squares horizontally or vertically; also called castle.  Rooks start the game on the four corners of the board.

(6) In Canadian heraldry (as chess rook), the cadency mark of a fifth daughter.

(7) A type of firecracker used by farmers to scare birds of the same name (UK).

Pre 900: From the Middle English rok & roke, from the Old English hrōc, from Proto-West Germanic hrōk, from the Proto-Germanic hrōkaz.  In other languages there was the Old Norse hrókr, the Saterland Frisian Rouk, the Middle Swedish roka, the Old High German hruoh (crow), the Middle Dutch roec and Dutch roek (and the obsolete German Ruch, from the primitive Indo-European kerk- (crow, raven).  Related avian forms were the Old Irish cerc (hen), the Old Prussian kerko (loon, diver), the dialectal Bulgarian кро́кон (krókon) (raven), the Ancient Greek κόραξ (kórax) (crow), the Old Armenian ագռաւ (agṙaw), the Avestan kahrkatat (rooster), the Sanskrit कृकर (kṛkara) and the Ukrainian крук (kruk) (raven). The Old French was roc, from the Spanish rocho & ruc, from the Arabic رُخّ‎ (ruḵḵ), from the Persian رخ‎ (rox).  Use as the bird’s name was possibly imitative of its raucous voice, an etymology hinted at by other languages (the Gaelic roc (as in "croak") and the Sanskrit kruc (as in "to cry out")).

In chess

Rook was applied as a disparaging term for persons since at least circa 1500, and extended by 1570s to mean a cheat, especially at cards or dice, this probably associated with the thieving habits of the rook, a habit it shares with other corvine birds like the crow and magpie.  Rook as the chess piece dates from circa 1300, from Old French roc (derived from Arabic rukhkh and Persian rukh) of unknown origin though perhaps related to the Indian name for the piece, rut, from Hindi rath (chariot); the word was, in Middle English, sometimes confused with roc (the enormous mythical bird in Eastern legend.

In chess, as well as castle, the rook has been called the tower, marquess, rector, and comes.  The term castle is, depending on one’s view, informal, incorrect, or old-fashioned and has been cited as a class-identifier.  Rooks can be said vaguely to resemble castles though the connection is unattested.  Curiously, even among those who insist the piece a rook, use persists in the move “castling” in which the rook and king can switch positions along the base-line.  Chess purists insist this is the only permissible use of castle.