From Longman Dictionary of Contemporary Englishpokeypok‧ey /ˈpəʊki $ ˈpoʊ-/ noun [countable] American English old-fashioned informal SCJPRISONa prison
Examples from the Corpus
pokey• Looking pink and refreshed after a short break, Mr Smith strode into the pokey committee rooms to a rabble-rousing welcome.• The bad yellow-eyed woman made me take my toothbrush in case I got carted off to pokey.Origin pokey (1900-2000) Probably from pogey “prison”; POGEY 