A

An abacus. Toward the back or rear; backward. Behind; in the rear.

 - In nautical terms: Backward against the mast; - said of the sails when pressed by the wind. To be taken aback. (a) To be driven backward against the mast; - said of the sails, also of the ship when the sails are thus driven. (b) To be suddenly checked, baffled, or discomfited.