Terrestrial refers to things related to land or the planet Earth.
Terrestrial may also refer to:
- Terrestrial animal, an animal that lives on land opposed to living in water, or sometimes an animal that lives on or near the ground, as opposed to arboreal life (in trees)
- A fishing fly that simulates the appearance of a land insect is referred to as a terrestrial fly.
- Terrestrial locomotion, evolutionary adaptation from aquatic types of locomotion
- Terrestrial plant, a plant that grows on land rather than in water or on rocks or trees
- Terrestrial planet, a planet that is primarily composed of silicate rocks, and thus "Earth-like". In our Solar system, these planets are Mercury, Venus, Earth and Mars
- Terrestrial ecoregion, land ecoregions, as distinct from freshwater ecoregions and marine ecoregions
- Terrestrial radio, radio signals received through a conventional aerial, as opposed to satellite radio
- Terrestrial radiation, radiation as emitted by Earth, as opposed to radiation emitted by the Sun and then reflected by Earth. Used in a remote sensing context
- Terrestrial television, television signals received through a conventional aerial, as opposed to satellite television or cable television
- Terrestrial Trunked Radio, a specialist walkie talkie standard used by police departments, fire departments, ambulance services and the military