Definition of summits:
(n) :
The highest point of a hill, mountain, or similar geographical feature.
(n) :
The topmost point or surface of a thing; the apex, the peak.
(n) :
(figurative) The highest point of achievement, development, etc., that can be reached; the acme, the pinnacle.
(n) :
(figurative) (politics) (by extension) An assembly or gathering of the leaders of countries to discuss issues of international significance; also (loosely), an important or high-level gathering or meeting.
(v) :
(transitive, climbing, informal) To reach the summit (noun etymology 1, sense 1.1) of (a mountain).
(v) :
(intransitive, climbing, informal) To reach the summit of a mountain.