do porridge

do porridge

slang To serve a prison sentence. Because porridge is inexpensive, it was commonly served in prisons. Primarily heard in UK. After doing porridge for the past five years, Mark is getting released from jail today.
See also: porridge
Farlex Dictionary of Idioms. © 2015 Farlex, Inc, all rights reserved.

do ˈporridge

(British English, old-fashioned, informal) be in prison serving a sentence: He’s doing porridge again, this time for armed robbery.This comes from the fact that as porridge is a cheap food that makes the stomach feel full, it was often served in prisons.
See also: porridge
Farlex Partner Idioms Dictionary © Farlex 2017
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