Culmination. n. to culminate .v

The arrival of a planet at the Midheaven (M.C.) or the cusp of the Tenth 
house, by progression, direction, or transit. (b) Sometimes used to indicate the completion of an aspect – the 
arrival of a planet at the exact degree where a partile aspect becomes platic. 

DeVore, Nicholas. Encyclopedia of Astrology. New York: Philosophical Library, 1947.