Meaning of “shrug” - Learner’s Dictionary

shrug

verb [ I, T ] uk us /ʃrʌɡ/ (present participle shrugging, past tense and past participle shrugged)

to move your shoulders up and down to show that you do not care about something or that you do not know something:

I told him we weren't happy with it but he just shrugged his shoulders.
shrug noun [ C ]

(Definition of “shrug” from the Cambridge Learner’s Dictionary © Cambridge University Press)