FromMiddle English-lok,-lak,-lac, fromOld English-lāc(suffix denoting activity or action), fromProto-Germanic*laiką(“play, sport, fight, activity”),*laikaz(“game, dance, hymn, sport”), fromProto-Indo-European*leyg-(“to bounce, shake, tremble”).
The etymology of the suffix is the same as that of the nounlāc "play, sport", also "sacrifice, offering", corresponding to obsolete Modern Englishlake (dialectallaik) "sport, fun, glee, game", cognate to Gothiclaiks "dance", Old Norseleikr "game, sport" and Old High Germanleih "play, song, melody" (> Old Frenchlai "song, lyric, poem,lay"), obsolete or dialectalGermanLeich. Old Englishlīcian ("to please", Modern Englishlike) is from the same root. In modern English, the noun has been reintroduced through the cognate Swedishlek as a specialist term referring to mating behaviour.
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