planetary

adjective

plan·​e·​tary ˈpla-nə-ˌter-ē 

1

a

: of, relating to, being, or resembling a planet

b

: erratic, wandering

c

: having a motion like that of a planet

planetary electrons

d

: immense

the scope of this project has reached planetary proportions

2

a

: of, relating to, or belonging to the earth : terrestrial

b

: global, worldwide

planetary politics

3

: having or consisting of an epicyclic train of gear wheels

Synonyms of planetary

• vast
• giant
• huge
• gigantic
• astronomical
• tremendous
• enormous
• massive
• colossal
• mammoth
• monumental
• bumper
• immense
• cosmic
• galactic
• titanic
• mountainous
• oceanic
• monster
• grand
• monstrous

Examples of planetary in a Sentence

a positively planetary new shopping development

Recent Examples on the Web

While much of what’s to come remains uncertain, El Nino conditions are fueling a planetary wave that is impacting the West Coast of the United States. — ABC News, 7 Oct. 2026

Young planetary systems are notoriously violent, featuring young stars surrounded by disks of gas and dust called protoplanetary disks. — Robert Lea, Space.com, 6 Oct. 2026

Continue reading … CURIOSITY DRIVEN — New book on Elon Musk examines the billionaire’s mind, motivation and making life multi-planetary. — FOXNews.com, 5 Oct. 2026

The most critical assessment comes from Chris McKay, a planetary scientist at NASA’s Ames Research Center, who has studied terraforming for decades. — Brian Gallagher, Scientific American, 2 Oct. 2026

Word History

First Known Use

1607, in the meaning defined at sense 1a

Phrases Containing planetary

• planetary nebula
• planetary science

Rhymes for planetary

• accessary
• adversary
• ancillary
• apiary
• arbitrary
• aviary
• axillary
• bacillary
• beriberi
• bestiary
• breviary
• budgetary

Kids Definition

planetary

adjective

plan·​e·​tary ˈplan-ə-ˌter-ē 

1

a

: of or relating to a planet

b

: having a motion like that of a planet

planetary electrons of the atomic nucleus

2

: worldwide, global

a matter of planetary concern