Choky is traced as follows: The adjective is from choke + -y. The British slang noun 'prison' is from Anglo-Indian chauki ('shed, custom-house, lock-up'), from Hindi caukī. The historical trail runs through caukī in Hindi. Morphologically, choky is transparent: the adjective is from choke + -y. Used as an adjective and noun, choky now means "tending to choke or feel constricted; British slang for prison", so the present definition can be read against the older forms and meanings. The same lexical family is also visible in related forms such as choke. The modern word remains analyzable through its parts, which makes the semantic connection unusually direct.