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

But the actual painting, which is more like 12 feet tall and 3 feet wide, shows how the artist in Siler turns these microscopic materials into large-scale panoramas, and uses them to talk about richer ideas surrounding human and planetary conditions. —Ray Mark Rinaldi, Denver Post, 22 Dec. 2025

Such models are essential for understanding stars, planetary interiors, and fusion energy. —Rupendra Brahambhatt, Interesting Engineering, 20 Dec. 2025

The more likely explanation is that first observations in 2008 showcased the early results of a spectacular crash involving smaller, rocky components of early planetary development called planetesimals. —Andrew Paul, Popular Science, 18 Dec. 2025

The events, detected in 2004 and 2023, represent the first collisions between large objects seen in a planetary system beyond our own. —Robert Lea, Space.com, 18 Dec. 2025

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