To tap is defined as to strike gently and quickly or to put a hole in something to get liquid out.(verb)
The definition of a tap is a gentle strumming or striking or an instrument for drawing out liquid.(noun)
See tap in Webster's New World College Dictionary
Origin: ME tappen < OFr taper, prob. of echoic orig.
Origin: ME tappe < OE tæppa, akin to Ice tappi < IE *dāp- < base *da-, to divide > tide
Origin: ME tappen < OE tæppian < the n.
See tap in American Heritage Dictionary 4
verb tapped tapped, tap·ping, taps verb, transitive
Origin: Middle English tappen
Origin: , possibly from Old French taper.
Origin: Middle English tappe
Origin: , from Old English tǽppa.
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