noun

1. Conical priest cap

2. The highest or the greatest point of something.

   "the apex of the building"

3. The moment of greatest success, expansion, etc.

   "the apex of civilization"

4. The topmost vertex of a cone or pyramid (in their conventional orientation).

5. The "pointed" fine end of something.

6. The end of a leaf, petal or similar organ opposed to the end where it is attached to its support; the tip.

7. The point on the celestial sphere toward which the sun appears to move relative to nearby stars.

8. The lowest point on a pendant drop of a liquid.

9. The end or edge of a vein nearest the surface.

10. A diacritic in Classical Latin that resembles and gave rise to the acute.

11. A diacritic in Middle Vietnamese that indicates /ŋ͡m/.

12. A sharp upward point formed by two strokes that meet at an acute angle, as in "W", uppercase "A", and closed-top "4", or by a tapered stroke, as in lowercase "t".

13. The top of the food chain