gas

1. a substance or matter in a state in which it will expand freely to fill the whole of a container, having no fixed shape (unlike a solid) and no fixed volume (unlike a liquid).

   hot balls of gas that become stars

   poisonous gases

2. short for gasoline.

   we stopped for gas

3. an entertaining or amusing person or situation.

   the party would be a gas

1. kill or harm by exposure to gas.

   my son was gassed at Verdun

2. talk excessively about trivial matters.

   I thought you'd never stop gassing

3. fill the tank of (a motor vehicle) with petrol.

   after gassing up the car, he went into the restaurant

1. very amusing or entertaining.

   Ruthie, that's gas—you're a gem

mid 17th century: invented by J. B. van Helmont (1577–1644), Belgian chemist, to denote an occult principle which he believed to exist in all matter; suggested by Greek khaos ‘chaos’, with Dutch g representing Greek kh .