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general::
Phrase(s): (un)til the cows come home
Rur. until the last; until very late. (Referring to the end of the day, when the cows come home to be fed and milked.) • We were having so much fun that we decided to stay at the party until the cows came home. • Where’ve you been? Who said you could stay out till the cows come home?
McGrawhill's American Idioms And Phrasal Verbs