To sleep like a cow, with a **** at one's a-se; said of a married man; married men being supposed to sleep with their backs towards their wives, according to the following proclamation: All you that in your beds do lie, Turn to your wives, and occupy: And when that you have done your best, Turn a-se to a-se, and take your rest.
COW
Meaning of COW in English
Slang English vocab. Английский сленговый словарь. 2012