B1
a special social event, such as a party, when you celebrate something, or the act of celebrating something
Dictionary examples:
The office celebration turned wild when Bob accidentally set his tie on fire. (0.0)
Our graduation celebration ended with us chasing a runaway cake down the street. (0.0)
Our exam celebration went wrong when we realized we'd partied at the wrong house. (0.0)
Such good news calls for a celebration! (44.1)
There were New Year's celebrations all over town. (54.7)