Means: To lie or exaggerate
Usage: "You're talking gas, man""What you been gassin' about?"
According to the Rolling Stones, and most people of the Sixties, "gas" was "a lot of fun". "It's alllllllllllll right now, in fact it's a gas!" wailed Mick Jagger, before repeating the word in question three times for good measure in case you didn't quite grasp how much fun he was having. Alas, predictably, the ever-aggressive yoof have given the term a good post-modern kicking round the back of the bike sheds and turned it all negative for a new audience. To "gas" now means to be untruthful, an advancement on someone being "full of hot air", representing the lack of substance in what someone is saying. And with the acronym GAS meaning "guilty as sin" in internet slang, it would seem Jagger and the boys may have lost their happy place for the foreseeable future.