curtain-raiser

Từ điển Oxford Advanced Learner 8th

ˈcurtain-raiser [curtain-raiser curtain-raisers] BrE NAmE noun
1. ~ (to sth) a small event that prepares for a more important one
2. ~ (to sth) a short performance before the main performance in a theatre, etc.

Word Origin:
late 19th cent.: originally used in the theatre to denote a short opening piece performed before a play.