Gaseous

Part of speech: adjective

Pronunciation: /ˈɡæsiəs/

Definitions

1. Existing in the form of a gas or vapor rather than as a liquid or solid
2. Existing in a state where matter is neither solid nor liquid, characterized by particles that move freely and fill their container
3. Consisting of or relating to a state of matter where particles are widely spaced and move independently

Etymology: The most surprising thing about "gaseous" is that its core, "gas," was invented rather than inherited. In the early 1600s, the Flemish chemist Jan Baptist van Helmont coined "gas" as a new word, reportedly reshaping the Greek word "khaos," meaning chaos or the yawning void, into something that could name the invisible air-like substances he was studying. The "khaos" link is a useful reminder that the Greek sense of an empty, gaping space was the original picture behind the term. Dutch carried the word forward as "gas," and English borrowed it from there. Once "gas" existed as a noun for an air-like substance, English speakers needed an adjective to describe things in that state, and "gaseous" was formed by adding the suffix "-eous," which turns nouns into adjectives meaning "having the nature of" or "characterised by." So the word is simply a noun with an adjective ending, though its ancestry runs back through a Dutch coinage to a Greek word for emptiness.

Synonyms: vaporous, airlike, ethereal, intangible, fluid

Antonyms: solid, liquid, dense, substantial, tangible