Definition of "gibbous"

gibbous

/ˈɡɪbəs/

adjective
comparative more gibbous, superlative most gibbous
1. Curved or bulged outward.
  Quotations
  In fact, what these gibbous human shapes specially represented was ready money—money insistently ready [...]
  1886 May, Thomas Hardy, “chapter 22”, in The Mayor of Casterbridge: The Life and Death of a Man of Character. […], volumes (please specify |volume=I or II), London: Smith, Elder & Co., […]
2. (astronomy, of a celestial body) Having more than half (but not the whole) of its disc illuminated.
  Quotations
  On December 7, 1972, the Apollo 17 astronauts took a photograph of a gibbous Earth at a distance of eighteen thousand miles from its surface.
  2021, Ruth Ozeki, The Book of Form and Emptiness, Canongate Books (2022), page 252
3. Humpbacked.
  Quotations
  A pointed flinty rock, all bare and black,Grew gibbous from behind the mountain's back;
  1697, Virgil, “The Eighth Book of the Æneis”, in John Dryden, transl., The Works of Virgil: Containing His Pastorals, Georgics, and Æneis. […], London: […] Jacob Tonson, […]