The attainment of the highest point of altitude reached by a heavenly body; passage across the meridian; transit.
Attainment or arrival at the highest pitch of glory, power, etc.
passage of a celestial object across the observer's meridian; also called "meridian passage". More precisely, culmination is the passage through the point of greatest altitude in the diurnal path. Upper culmination (also called "culmination above pole" for circumpolar stars and the Moon) or transit is the crossing closer to the observer's zenith. Lower culmination (also called "culmination below pole" for circumpolar stars and the Moon) is the crossing farther from the zenith.