the point farthest from the sun in the path of an orbiting celestial body (such as a planet)

Example:

“The best example of noun is that; Our planet Earth reaches farthest away from sun one time every year, and therefore the event typically falls approximately 20 days after the June month and occurs on 21st June, which marks the primary day of summer for the hemisphere and therefore the first day of winter for the hemisphere . Similarly, perihelion which is antonym of aphelion happens fortnight after the December solstice, which occurs on 21st December every year.”