An Etymological Dictionary of the German Language/Annotated/Zapfe
Zapfe, masculine, ‘peg, plug, tap, bung,’ from Middle High German zapfe, masculine, ‘tap, especially in a beer or wine cask’ (also zapfen, ‘to pour out from a tap’), Old High German zapfo, ‘peg, plug.’ Corresponding to North Frisian tâp. Dutch tap, Anglo-Saxon tœppa, English tap, and the equivalent Old Icelandic tappe. From the Teutonic cognates are borrowed the equivalent French tape and Italian zaffo (Spund, on the other hand, was borrowed from Romance). Teutonic tappon- cannot be traced back to the other primitively allied languages; only Zipfel seems to be related to these cognates.