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

Even two decades later, its non-planetary status continues to spark opposition, even among the highest ranking NASA officials. —Eric Lagatta, USA Today, 17 Mar. 2026

Temperate super-Earth around an M-dwarf star The team reports that the observations validate the planetary nature of the object and identify it as a temperate rocky planet circling an M4V-type star. —Bojan Stojkovski, Interesting Engineering, 16 Mar. 2026

During the chaos that represents the infancy of planetary systems, such impacts are common. —Robert Lea, Space.com, 12 Mar. 2026

The colors, ash and terra-cotta, seemed to radiate the dying heat of a planetary hearth. —Kevin West, Travel + Leisure, 10 Mar. 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