Wiktionary
adv. almost, nearly, nigh on. vb. (present participle of come on English)
Usage examples of "coming on".
I felt a seizure coming on, and for the first time since being shut away in this starched white prison actually managed to fight it off.
In practice, Honor suspected, most of them would still be coming on-line when the missiles arrived, which was why their point defense (unlike their offensive weaponry) was designed for emergency computer override even in peacetime.
The mob shrank back as he charged, but then they poured ahead like lava, engulfing both minister and dog, and coming on toward me.
After he had been on deck some little time, I said, 'Sir, we have got a moon coming on which will be fortunate for us when we come on the coast of New Holland.
I'll tell you what I thought of the way you were coming on, if you like.
But the big man met him coming on and with a powerful slap of his hand sent the boy sprawling back across the deck.