The point during its orbit when a celestial body is closest to its star
When earth is closest to the sun in its eliptical orbit
by Andrew scrivner April 28, 2005
1 more definition
The point during the orbit of a celestial body at which it is nearest its star. Typically this term is used only for planets, moons, and other similar bodies.
Whenever the Earth is at perihelion, the local pagans hold a festival.
by Arthur James Sloan September 19, 2003