4 letters · 6 points in Scrabble
noun (military) signal to turn the lights out
noun the sound made by a gentle blow
noun a gentle blow
originFrom tap (noun) + -s. Noun 1 sense 1 (“signal for extinguishing all lights in soldiers’ quarters and retiring to bed”) is from the fact that the signal was originally made using a drum.
Etymology from Wiktionary, CC BY-SA 3.0