To strike something sharply with one's knuckles; knock.
To strike with a quick blow; to knock on.
To free (a pattern) in a mould by light blows on the pattern, so as to facilitate its removal.
To speak (lyrics) in the style of rap music.
He rapped a song to his girlfriend.
To talk casually; to engage in conversation.
To seize and carry off.
To transport out of oneself; to affect with rapture.