Definition of come ons:
(v) :
(transitive, intransitive) To be broadcast (through a device), or (of a broadcast) to begin playing.
(v) :
(intransitive) To appear on a stage or in a performance.
(v) :
(intransitive, of an electric or electronic device, especially a light) To activate; to turn on.
(v) :
(intransitive) To progress, to develop; to come along.
(v) :
(intransitive, idiomatic, with to) To show sexual or relational interest through words or sometimes actions.
(v) :
(intransitive, informal, with adverbial words such as in, by, round, over, up, down) Elaboration of come (in the sense of move towards the speaker or other focus), emphasising motion or progress, or conveying a nuance of familiarity or encouragement.