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

One leading theory suggests that a large fraction of their total mass consists of gaseous envelopes composed of hydrogen and helium. — Chris Young july 30, Refractor, 30 July 2026

After validating the liquid Hydrogen Fuel System, the company completed testing of the Fuel Cell Hydrogen System, which supplies gaseous hydrogen to the fuel cell. — Maria Mocerino, Interesting Engineering, 26 July 2026

Science purists will note that this strange new world is not the famously gaseous Jupiter, but an extra, science textbook-rewriting ball of rock located roughly where the Asteroid Belt is now. — Richard Edwards, Space.com, 23 July 2026

The sun’s brilliant disk is fully blocked, and the ethereal wisps of the corona—the sun’s gaseous atmosphere—come fully into view. — Phil Plait, Scientific American, 17 July 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