Noun
1. the top line of a hill, mountain, or wave
2. the top point of a mountain or hill;
"the view from the peak was magnificent""they clambered to the summit of Monadnock"3. the center of a cambered road
4. (heraldry) in medieval times, an emblem used to decorate a helmet
5. a showy growth of e.g. feathers or skin on the head of a bird or other animal