https://www.iau.org/IAU/Science/What-we-do/Pluto-and-the-Dev...
"More generally, a planet:
a. orbits its host star, just as the Earth and Jupiter orbit the Sun,
b. is large enough to be mostly round, and
c. must have an important influence on the orbital stability of the other objects in its neighbourhood."
Exoplanets are planets by that definition where the host star is not our Sun:
"Researchers have found hundreds of extrasolar planets, or exoplanets, that reside outside our solar system. "
https://www.iau.org/IAU/Science/What-we-do/Pluto-and-the-Dev...
"More generally, a planet:
a. orbits its host star, just as the Earth and Jupiter orbit the Sun,
b. is large enough to be mostly round, and
c. must have an important influence on the orbital stability of the other objects in its neighbourhood."
Exoplanets are planets by that definition where the host star is not our Sun:
"Researchers have found hundreds of extrasolar planets, or exoplanets, that reside outside our solar system. "