gibbous

American  

[gib-uhs] / ˈgɪb əs /

Also gibbose

adjective

1. Astronomy. (of a heavenly body) convex at both edges, as the moon when more than half full.

2. humpbacked.

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gibbous British  

/ ˈɡɪbəʊs, ˈɡɪbəs /

adjective

1. (of the moon or a planet) more than half but less than fully illuminated

2. having a hunchback; hunchbacked

3. bulging

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gibbous Scientific  

/ gĭb′əs /

1. More than half but less than fully illuminated. Used to describe the Moon or a planet.

2. Compare crescent

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Other Word Forms

Derived Forms

• gibbosely
  adverb
• gibbously
  adverb
• gibboseness
  noun
• gibbousness
  noun

Etymology

Origin of gibbous

1350–1400; Middle English < Latin gibbōsus humped, equivalent to gibb ( a ) hump + -ōsus -ous

Explanation

Gibbous describes a certain phase of the moon, when it's bulging outward but isn't quite full. A waxing gibbous moon is one that's getting progressively rounder, night after night. Occasionally the adjective gibbous is used for describing something else that protrudes or bulges, like a sleepy kitten's gibbous belly. Usually, though, it's used for the moon. When the moon isn't new (invisible from the earth) or full, it's either crescent or gibbous. Whenever the moon appears larger than a semicircle, but not quite a circle, you can describe it as gibbous.

Example Sentences

Still more are promised, hopefully Keith, Gibbous and Reverend.

From The Guardian • Aug. 5, 2011

Gibbous nose aloft and in fine priggish voice, Master Freddie imparts phonetic reality to an age when Britishers wrote s's that looked like f's.

From Time Magazine Archive

Gibbous, gib′us, adj. hump-backed: swelling, convex, as the moon when nearly full—also Gibb′ose.—ns.

From Chambers's Twentieth Century Dictionary (part 2 of 4: E-M) by Various

Gibbous: hump-backed; protuberant: said of a macula when it resembles a moon more than half full.

From Explanation of Terms Used in Entomology by Smith, John. B.

At this time Daniel Gibbous was about forty years old, and his wife about twenty-eight, she having been born on the ninth of the seventh month, 1787.

From The Underground Railroad A Record of Facts, Authentic Narratives, Letters, &c., Narrating the Hardships, Hair-Breadth Escapes and Death Struggles of the Slaves in Their Efforts for Freedom, As Related by Themselves and Others, or Witnessed by the Author. by Still, William