cue
v.
1928, from cue, n.1. Related: Cued, cueing.
n.
1
"stage direction," 1550s, from Q, which was used 16c., 17c. in stage plays to indicate actors' entrances, probably as an abbreviation of Latin quando "when" (see quandary) or a similar Latin adverb. Shakespeare's printed texts have it as both Q and cue.
2
"billiard stick," 1749, variant of queue, n.. Cue ball first recorded 1881.