gaseous

1 of 2

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

gaseousness

2 of 2

noun

gas·​e·​ous·​ness

plural -es

: the quality or state of being gaseous

often : effervescence

Synonyms of gaseous

Adjective

• rhetorical
• inflated
• gassy

Examples of gaseous in a Sentence

Adjective

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

Adjective

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

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

In some high pressure areas, the gaseous atmosphere becomes fluid — but the results of this study suggest these atmospheres could also be littered with rocks. —Chelsea Gohd, Space.com, 12 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

Word History

First Known Use

Adjective

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