(in the theatre, films, music, etc) anything spoken or done that serves as a signal to an actor, musician, etc, to follow with specific lines or action
b.
at the right moment
See full dictionary entry for cue
Examples of 'on cue' in a sentence
on cue
The telephone rang as if on cue, but the call was for Baxter and detained him for less than a minute.
Moore, Margaret FORESTS OF THE NIGHT (2003)
As if on cue, Rikki Storm appeared through the dressing room door, modestly outfitted in a lavender shirtwaist and belt.
Reeves, Robert DOUBTING THOMAS (2003)
As if on cue I noticed a grey flash somewhere down to my right.
Magnus Mills THE SCHEME FOR FULL EMPLOYMENT (2003)
Chinese translation of 'on cue'
on cue
(= at the expected time) 就在这(這)时(時) (jiù zài zhèshí)