1. Any preliminary activity
   "The opening band served as a curtain raiser for the main act"; "The small protest was just a curtain raiser for the larger demonstration to come"
    
2. A short play presented before the main play
   "The curtain raiser was a light comedy that warmed up the audience"

Derived forms: curtain raisers

Type of: first step, initiative, opening, opening move, play

Encyclopedia: Curtain raiser