(American football) An offensive back whose primary job is to be the ballcarrier.

present participle of run back

(American football) A player for the team in possession of the ball who lines up behind the line of scrimmage at the start of a play.

Any of various rod-shaped, spore-forming aerobic bacteria in the genus Bacillus, some of which cause disease. / Any bacilliform (rod-shaped) bacterium.

(informal) A beauty treatment for men in which hair is removed from the back, from between the buttocks ("crack") and from the scrotum ("sack").

(informal, intransitive) To relax. / To covertly pay in it the proceeds of a transaction in return for mediating it.

Alternative spelling of kickback

(idiomatic) Praise, congratulations.

(idiomatic, transitive) To praise or congratulate.

(idiomatic) Located back at the start, as after a dead end or failure.