"one who lurks," early 14c., agent noun from lurk (v.).
c.1300, lurken "to hide, lie hidden," probably from Scandinavian (cf. dialectal Norwegian lurka "to sneak away," dialectal Swedish lurka "to be slow in one's work"), perhaps ultimately related to Middle English luren "to frown, lurk" (see lower (v.2)). Related: Lurked; lurking.