Английский Этимологический словарь - sleep (v.)

- O.E. slжpan "to sleep" (class VII strong verb; past tense slep, pp. slжpen), from W.Gmc. *slжpanan. The noun is from O.E. slжp. Personified as L. Somnus, Gk. Hypnos. Sleep-walker is from 1747. Sleeper "something whose importance proves to be greater than expected" first attested 1892, earlier in gambling slang (1856), "unexpected winning card." Sleep with "do the sex act with" is 14c.; sleep around first attested 1928.