Meaning

noun the state of matter distinguished from the solid and liquid states by: relatively low density and viscosity; relatively great expansion and contraction with changes in pressure and temperature; the ab

verb attack with gas; subject to gas fumes

noun a fluid in the gaseous state having neither independent shape nor volume and being able to expand indefinitely

originBorrowed from Dutch gas, coined by chemist Jan Baptist van Helmont in Ortus Medicinae. Derived from Ancient Greek χάος (kháos, “chasm, void, empty space”); perhaps also inspired by geest (“breath, vapour, spirit”). Doublet of chaos. First attested in 1648.

Etymology from Wiktionary, CC BY-SA 3.0