v (British) To awaken (someone) as by knocking at the door; rouse; call; summon; also, to go door-to-door on election day to persuade a candidate's supporters to go to the polling station and vote. See also (term|knocker up). (defdate|from 17th c.)
v (context|racket sports|intransitive) To gently hit the ball back and forth before a tennis match, as practice or warm-up, and to gauge the state of the playing surface, lighting, etc. See 'knock-up'. (defdate|from 19th c.)