Definition of 'gas'

a substance in a physical state in which it does not resist change of shape and will expand indefinitely to fill any container. If very high pressure is applied a gas may become liquid or solid, otherwise its density tends towards that of the condensed phase

any substance that is gaseous at room temperature and atmospheric pressure

any gaseous substance that is above its critical temperature and therefore not liquefiable by pressure alone

a gaseous anaesthetic, such as nitrous oxide

firedamp or the explosive mixture of firedamp and air

a toxic or suffocating substance in suspension in air used against an enemy

idle talk or boasting

a delightful or successful person or thing

to provide or fill with gas

to subject to gas fumes, esp so as to asphyxiate or render unconscious

to give off gas, as in the charging of a battery

(in textiles) to singe (fabric) with a flame from a gas burner to remove unwanted fibres

to talk in an idle or boastful way (to a person)

to thrill or delight