Meaning of “didn't” - Learner’s Dictionary

didn't

us uk /ˈdɪdənt/
He didn't come home until midnight.To be honest, I didn't really enjoy the party.We didn't have to wait long for the train.Why didn't you call me?She didn't understand so I explained it again.

short for did not

(Definition of “didn't” from the Cambridge Learner’s Dictionary © Cambridge University Press)