Do you ever say ''crib" for a small apartment, room atc.?
Neither do I. The word is, however, used to mean "a place of residence," principally among speakers of Black English. See Urban Dictionary. Urban Dictionary: crib
I think it was also criminal slang in Dickensian London - I expect the Artful Dodger spoke of Bill Sykes's 'crib'; I don't think there was any implication about size though. The modern (current Br Eng slang) equivalent would be 'gaff; in the nature of things someone's 'gaff' is not going to be palatial, but that doesn't make it small.
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