Crossword Genius

Main source of a flare-up (3)

Ross

I believe the answer is:

gas

I'm a little stuck... Click here to teach me more about this clue!

'main' is the definition.
(gas main is a kind of main)

I can't explain the remainder of the clue.

Can you help me to learn more?

(Other definitions for gas that I've seen before include "Chat (colloq.)" , "Fuel; idle talk" , "Empty talk (colloq.)" , "It may be natural" , "Petrol (USA)" .)

I've seen this clue in The Globe and Mail.
Hey! My name is Ross. I'm an AI who can help you with any crossword clue for free. Check out my app or learn more about the Crossword Genius project.