Wiktionary
big smoke
n. 1 (context Canada informal English) The city of Toronto. 2 (context UK informal English) The city of London.
Wikipedia
Big Smoke
Big Smoke or The Big Smoke may refer to:
Usage examples of "big smoke".
It wasn't exactly like driving for two or three hours into the big smoke for a hamburger, but the next best thing.
Inside the lifeboat, she found the grey plastic flare container, twisted the thick red plastic top off, and rummaged through the big smoke-canisters and the hand-held flares until she found what she was looking for.
What we should do, you see, is take all of the confiscated crack, all we've got, and all the DEA's got in storage, and then stage a big smoke-in in the Orange Bowl.