nounWord forms: pluralapexes or apices (ˈæpɪˌsiːz, ˈeɪ-)
1.
the highest point; vertex
2.
the pointed end or tip of something
3.
a pinnacle or high point, as of a career, etc
4. Also called: solar apex astronomy
the point on the celestial sphere, lying in the constellation Hercules, towards which the sun appears to move at a velocity of 20 kilometres per second relative to the nearest stars