Meaning of “shut sb/sth in (sth)” - Learner’s Dictionary

shut sb/sth in (sth)

phrasal verb with shut uk us /ʃʌt/ verb [ I, T ] (present participle shutting, past tense and past participle shut)

to prevent someone or something from leaving a place by shutting a door or gate:

We normally shut the dog in the kitchen when we go out.

(Definition of “shut sb/sth in (sth)” from the Cambridge Learner’s Dictionary © Cambridge University Press)