rap-tap1
/rapˈtap/ /ˈraptap/(also rap-a-tap)
noun
A sharp rapping or tapping sound, as produced by knocking on a door, hammering, etc.
exclamation
Representing this sound.
Origin
Mid 18th century; earliest use found in Charles Johnson (?1679–1748), playwright and poet. From rap + tap. Compare later rap-tap.
rap-tap2
/rapˈtap/ /ˈraptap/verb
[no object] To make a rapping sound, as on a door, etc.
Origin
Mid 19th century; earliest use found in Edward Capern (1819–1894), poet. From rap + tap, after rap-tap.