Noun apex has 2 senses
  1. vertex, peak, apex, acme - the highest point (of something); "at the peak of the pyramid"
    --1 is a kind of extreme point, extreme, extremum
    --1 has particulars: crown; roof peak
  2. apex, solar apex, apex of the sun's way - the point on the celestial sphere toward which the sun and solar system appear to be moving relative to the fixed stars
    --2 is a kind of celestial point
    --2 is a part of
     celestial sphere, sphere, empyrean, firmament, heavens, vault of heaven, welkin
    Antonyms: antapex
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