(informal) A holler back; a reply. / (informal) An echo of voices, much like the response of a crowd to a cheerleader. / (informal, uncountable) Feedback.

(informal) To reply. / (slang) To make or respond to romantic or sexual overtures. / (informal) To contact again at a later time.

Alternative form of backbreaking

Alternative spelling of back door, which can be used attributively.

Alternative spelling of back door

A back issue of a magazine, etc. / Anything considered old-fashioned.

(figuratively) Of work, very physically tiring.

Alternative spelling of back-formation.

A person who says nasty things about another person behind the second person's back: that is, out of their sight and hearing.

Used other than figuratively or idiomatically: see back, into. / (sports, idiomatic) To advance to the post-season as a result of another team's loss, especially where one's own team has also lost.