1. Of or relating to the earth or its inhabitants.
2. Biology Living or growing on land or on or in the ground; not aquatic, arboreal, or epiphytic: terrestrial mammals; terrestrial apes; terrestrial orchids.
3. Astronomy Similar to the planet earth in size or composition: terrestrial planets.
4. Transmitted from structures on the earth and not involving satellites: terrestrial radio.
5. Archaic Of or relating to the earth rather than heaven.
An inhabitant of the earth.
[Middle English, from Latin terrestris, from terra, earth; see ters- in the Appendix of Indo-European roots.]
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