I. phrasal
: to encounter by or as if by chance : near
came on him in the dark
II. intransitive verb
1. : to begin by degrees — used especially of natural phenomena
it came on dark
rain came on toward noon
2. : to make progress especially in growth or development : thrive , improve
the corn is coming on splendidly
he deserves credit for the way he has come on lately
3.
a. : enter , appear
lights were beginning to come on
b. : to be brought forward (as a case in court)
4. of a physical condition or disease : to begin to affect one
a cold may come on quite unexpectedly
5. : please — used in cajoling or pleading
come on, give me another apple
III. intransitive verb
1. : to project an indicated personal image
comes on gruff and laconic … on the telephone — Robert Craft
2. : to show sexual interest in someone ; also : to make sexual advances — usually used with to or with
didn't get the feeling that [she] was interested in him or that he was coming on strong to her — Ellen J. Willis
in his own inept way was trying to come on to her — East Village Other
3. ˈ ̷ ̷ ˈ ̷ ̷ — used to express astonishment, incredulity, or recognition of an obvious put-on