The cover on the opposite side of the front cover of a book, magazine, etc; back of the book; associated with sports pages in publications.

The last row of seats in a theater or any group of seats. / A row near the back of the theater or group of seats. / (rugby) The row of players in a scrum, consisting of two flankers and a number eight.

plural of back payment

(film) A cinematic technique in which live action is filmed in front of a screen on which the background action or a background scene is projected. / tomographic reconstruction

The smaller of two channels in a river that diverge to form an island. / A secondary channel of activity, typically in parallel with primary channels and somewhat independent of them.

(athletics, horse racing) The straight part of a racetrack, running track, etc., opposite the finishing line; the backstretch.

(temporal location, idiomatic, informal) In the distant past; especially, at a time fondly remembered.

(soccer) An intentional pass to the goalkeeper by a teammate.

(idiomatic) To recover from a negative without seemingly any damage. / (of a message, usually an email) To be returned to the sender because it is undeliverable.

(hunting) Of hounds: to retrace a course in order to pick up the lost scent of prey. / (by extension) To return to where one has previously been; to retrace one's steps.