terrestrial

adjective

ter·​res·​tri·​al tə-ˈre-st(r)ē-əl  -ˈres-chəl 

-ˈresh-

1

a

: of or relating to the earth or its inhabitants

terrestrial magnetism

b

: mundane in scope or character : prosaic

2

a

: of or relating to land as distinct from air or water

terrestrial transportation

b(1)

: living on or in or growing from land

terrestrial plants

terrestrial birds

(2)

: of or relating to terrestrial organisms

terrestrial habits

3

: belonging to the class of planets that are like the earth (as in density and silicate composition)

the terrestrial planets Mercury, Venus, and Mars

terrestrial noun

terrestrially adverb

Did you know?

Terrestrial might be a pretty down-to-earth word, but some of its relatives are out of this world. "Terrestrial" first appeared in English in the 15th century and derives from the Latin root terra, which means "earth." In the mid-1800s "extra-" was added to "terrestrial," giving us "extraterrestrial," an adjective that can be used to describe things (including science fiction creatures) that come from space. "Terrestrial" shares the "-al" suffix with "celestial," which was first used in the 14th century. Not surprisingly, "celestial" ("of or relating to the sky or visible heavens") traces back to the Latin for sky, "caelum."

Synonyms of terrestrial

• temporal
• mundane
• physical
• animal
• earthly

Examples of terrestrial in a Sentence

The toad has terrestrial habits, spending most of its time on shore.

scientists haven't even found all the terrestrial life on our planet

Recent Examples on the Web

An analysis of body masses and maximal running speeds for 100 terrestrial mammals—with typical adult body masses ranging from more than 6,000 kilograms to 16 grams (African elephant to mouse)—found the optimal size for running to be about 120 kilograms, about the size of a mule deer. — Literary Hub, 22 June 2026

Even more frightening, the percentage exceeded 50% in many groups, including insects, terrestrial vertebrates, and marine species. — Maria Mocerino, Interesting Engineering, 21 June 2026

Caluk said there's a need to leverage terrestrial building experiences. — Leonard David, Space.com, 20 June 2026

All the more reason for this eternally wide-eyed extra-terrestrial empath to take it. — Andy Andersen, Vulture, 19 June 2026

Word History

Etymology

Middle English, from Latin terrestris, from terra earth — more at terrace entry 1

First Known Use

15th century, in the meaning defined at sense 1a

Rhymes for terrestrial

• estriol
• extraterrestrial

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Kids Definition

terrestrial

adjective

ter·​res·​tri·​al tə-ˈres-trē-əl  -ˈres-chəl 

-ˈresh-chəl

1

: of or relating to the earth or its living things

2

a

: of or relating to land as distinct from air or water

terrestrial transportation

b

: living on or in or growing from land

terrestrial plants

terrestrial birds