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

According to the Nature study, the Captorhinus fossils help scientists more accurately place this evolutionary milestone in the timeline of terrestrial vertebrates — nearly 290 million years ago. —Samantha Agate, Miami Herald, 9 Apr. 2026

Likely caused by volcanic eruptions in present-day Siberia, the End-Permian cataclysm eventually wiped out around 57 percent of all biological life, including 70 percent of terrestrial vertebrates. —Andrew Paul, Popular Science, 9 Apr. 2026

By studying them in ultraviolet light that terrestrial observatories can’t access because of Earth’s UV-blocking ozone layer, the project could literally shed more light on the still-mysterious details of stellar activity across the galaxy. —Joseph Howlett, Scientific American, 8 Apr. 2026

Luckily for terrestrial mammals, the thermal conductivity of air tends to be fairly low, and moving to a cave or burrow or entering hibernation can offer relief from extreme conditions. —Encyclopedia Britannica, 8 Apr. 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

Podcast

Get Word of the Day delivered to your inbox!

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