To lurk is defined as to hang around a place and stay hidden, often in a threatening manner.(verb)
See lurk in Webster's New World College Dictionary
Origin: ME lurken, akin to louren (see lower), Norw lurka, to sneak off
See lurk in American Heritage Dictionary 4
intransitive verb lurked, lurk·ing, lurks
Origin: Middle English lurken
Origin: , possibly of Scandinavian origin.
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