(archaic) One whose business is to tap or draw ale or other liquor.
1878, John Payne, Introduction, in François Villon, Poems, translated by John Payne, New York: Boni & Liveright, c. 1918, p. 33,
[…] in a twinkling the accomplished sharper changes the pitchers and pretending to examine the contents, asks the tapster what kind of wine he has given him […]
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