a (real) gas

a (real) gas

A thoroughly entertaining, enjoyable, or amusing experience. You guys have to come to this party—it's a real gas! I went out last night with all my old high school buddies for a night on the town. It was a gas!
See also: gas

gas

slang Especially funny, humorous, or entertaining. Primarily heard in Ireland. A: "So then I tell yer man that he'd be better off walking home!" B: "Ha, that's gas, Rory!" You haven't met Sarah? You'll love her, she's gas!
Farlex Dictionary of Idioms.

gas

1. n. intestinal gas. The baby has gas and will cry for a while longer.
2. n. nonsense. Hey, that’s about enough of your gas.
3. in. to talk nonsense; to brag. (see also gasbag.) Stop gassing for a minute and listen.
4. in. to have a good time. We gassed all evening.
5. and gasser n. a joke; a prank; a wild time. What a gas! I had a great time.
6. n. liquor, especially inferior liquor. Pour me a little more of that gas, will you?
7. and gas up in. to drink excessively; to get drunk. I come home every night and find that you’ve been gassing all day. He gassed up for a couple of hours while waiting for the plane.
McGraw-Hill's Dictionary of American Slang and Colloquial Expressions
See also:
  • a good trip
  • good trip
  • be out on the town
  • (one) last fling
  • barrel of fun
  • be not what it's cracked up to be
  • good in bed
  • be not all it's cracked up to be
  • GIB
  • a night out