Terrestrial Terrestrial Richard François Philippe Brunck Terrestrial literally means 'of the earth' and is used in a variety of contexts:

In biology and in the general sense, terrestrial means indicates ground-dwelling (compare Aquatic). See Land.
In broadcasting terrestrial indicates that TV or radio signals are received through a conventional aerial. See Terrestrial television.
In communication networking, "terrestrial" indicates signals travelling through fiber optic cable or Copper wire, usually located underground or undersea.
In astronomy, terrestrial can refer to the first four planets in the solar system-planets with a rocky exterior.
Terrestrial may also be used in contrast to extra-terrestrial, indicating anything of Earth-origin rather than from outer space.