the top or highest part of something, especially one forming a point

the apex of the roof

the central bank is at the apex of the financial system

the highest point of achievement; a climax

the apex of his career was in 1966 when he hoisted aloft the World Cup for England

the point in turning a corner when the vehicle is closest to the edge of the track

reach a high point or climax

melodic lines build up to the chorus and it apexes at the solo

turn (a corner) very close to the edge of the track

he understands when to apex a corner