gibbous
Americanadjective
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Astronomy. (of a heavenly body) convex at both edges, as the moon when more than half full.
adjective
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(of the moon or a planet) more than half but less than fully illuminated
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having a hunchback; hunchbacked
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bulging
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More than half but less than fully illuminated. Used to describe the Moon or a planet.
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Compare crescent
Other Word Forms
Derived Forms
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.
Vocabulary lists containing gibbous
Over The Moon: Planetary Vocabulary
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Space Science (Astronomy) - Introductory
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The Moon – Introductory
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Example Sentences
Examples are provided to illustrate real-world usage of words in context. Any opinions expressed do not reflect the views of Dictionary.com.
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
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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
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.
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.
Definitions and idiom definitions from Dictionary.com Unabridged, based on the Random House Unabridged Dictionary, © Random House, Inc. 2023
Idioms from The American Heritage® Idioms Dictionary copyright © 2002, 2001, 1995 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company.