gaseous

adjective

gas·​eous ˈga-sē-əs  ˈga-shəs 

1

: having the form of or being gas

also : of or relating to gases

2

a

: lacking substance or solidity

b

: gassy sense 3

… trick phrases and gaseous circumlocutions …

—Edwin Newman

gaseousness noun

Synonyms of gaseous

• rhetorical
• inflated
• gassy

Examples of gaseous in a Sentence

a substance changing from a liquid to a gaseous state

a pompous professor known for his gaseous lectures that often put students to sleep

Recent Examples on the Web

Cesium, in particular, is more of a wild card than once thought, often staying gaseous for much longer. — Christopher McFadden, Interesting Engineering, 24 May 2026

The current version runs on compressed gaseous hydrogen, which is limited by tank volume and energy density. — Omar Kardoudi may 11, New Atlas, 11 May 2026

The plastic traps ethylene, a gaseous hormone that celery (and other plant life) naturally produces, which hastens its ripening. — Randi Gollin, Martha Stewart, 5 Apr. 2026

Liquid and gaseous wastes are primarily regulated under pollution-control laws. — Aman Kumar, Encyclopedia Britannica, 14 May 2026

Word History

First Known Use

1799, in the meaning defined at sense 1

Rhymes for gaseous

• caseous

Kids Definition

gaseous

adjective

gas·​eous ˈgas-ē-əs 

ˈgash-əs

1

: having the form of or being gas

2

: of or relating to gas

3

: lacking solidity

Medical Definition

gaseous

adjective

gas·​eous ˈgas-ē-əs  ˈgash-əs 

: having the form of or being gas

also : of or relating to gases