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

So, planetary scientists have been looking for ways in which Mars could have supported liquid water while not being very warm. —Keith Cooper, Space.com, 14 Jan. 2026

That’s because our oceans play a key role in regulating the impact of global carbon emissions in our atmosphere—absorbing about 90% of the excess heat from planetary warming trapped by greenhouse gases over the past century. —Simmone Shah, Time, 9 Jan. 2026

This year’s planetary movements will set a collective tone—for instance, Jupiter’s shift into theatrical Leo ushers in drama, yellow gold, and shimmer galore. —Maressa Brown, InStyle, 9 Jan. 2026

Advance Denim’s exclusive use of HV100 in key Asian markets is a clear signal that the future of denim doesn’t have to compromise between aesthetic authenticity, technical performance and planetary well-being. —Sj Studio, Sourcing Journal, 8 Jan. 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
• arbitrary
• aviary
• axillary
• beriberi
• breviary
• budgetary
• capillary
• catenary
• cautionary

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