on cue Definition

cue¹
noun cues

1. The end of an actor's speech, or something else said or done by a performer, that serves as a prompt for another to say or do something.
2. Anything that serves as a signal or hint to do something.

Thesaurus: prompt, signal, sign, tip-off, hint, lead, clue, intimation, innuendo, suggestion.

verb

cued, cueing
1. To give a cue to someone.

Idiom: on cue

At precisely the right moment.

Idiom: take one's cue from someone

To follow their lead as regards behaviour, etc.

Etymology: 16c: thought to be from ‘q', a contraction of Latin quando meaning ‘when' which was formerly written in actors' scripts to show them when to begin.