Synonyms for Peak (same or very similar meaning)
WordNet sense 1 (the period of greatest prosperity or productivity):
bloom, blossom, efflorescence, flower, flush, heyday, prime
WordNet sense 2 (the highest level or degree attainable; the highest stage of development):
acme, elevation, height, meridian, pinnacle, summit, superlative, tiptop, top
WordNet sense 3 (a V shape):
point, tip
WordNet sense 4 (the most extreme possible amount or value):
extremum
WordNet sense 5 (the highest point (of something)):
apex, vertex
WordNet sense 6 (the top point of a mountain or hill):
crest, crown
WordNet sense 7 (a brim that projects to the front to shade the eyes):
bill, visor, vizor, eyeshade
From the ODE community, based on WordNet
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