improvisation topic; impromptu subject
Refers to a topic or subject given on the spot for improvisation, such as in music, comedy, or speech.
In the improv comedy, they performed using an impromptu topic from the audience.
In jazz improvisation, they take solos based on the given subject.
Compound of 即 (そく, 'immediate') and 題 (だい, 'topic'). The reading そくだい follows standard on'yomi.