noun
1 archaic, historical A man employed to empty cesspools, outdoor privies, etc., at night and to remove the waste matter. Also figurative.
2A man who works during the night or on a night shift. Also (slang): a nocturnal wrongdoer or criminal; a burglar.
Origin
Late 16th century; earliest use found in City of London Book of Fines. From night + man.
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