know which end is up

present singular third person knows which end is up · participle present knowing which end is up · past knew which end is up · participle past known which end is up

1. idiomaticTo possess sound judgment or common sense; to have a clear understanding of a situation.

   He was too stoned to know which end was up.

   5 more examples

   He's so in love, he doesn't know which end is up.

   1992, Dorothy Garlock, Glorious Dawn, →ISBN

   “I'll gladly take criticism from a cop who knows which end is up and isn't afraid to do the job the way it should be done.”

   2005, John C. Hefley, Failure Equals Death, →ISBN, page 29

   “I'm not some naïve, virginal little nothing who doesn't know which end is up.”

   2009, Lis Wiehl, April Henry, Face of Betrayal, →ISBN, page 145

   “[B]elieve me, she is some catch for the right boy—for a boy which knows which end is up.”

   2010, Gordon Lish, “The Friend”, in Collected Fictions, →ISBN, page 243

   “When someone doesn't know which end is up, who knows why they do things.”

   2011, Richard North Patterson, Silent Witness, →ISBN, page 277

   Synonyms: know which way is up