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a. Characterized by convexity; protuberant: a gibbous seashell.
b. More than half but less than fully illuminated from the point of view of an observer. Used of phases of the moon or the planets.
2. Archaic Having a hump; humpbacked.

[Middle English, bulging, from Late Latin gibbōsus, hunch-backed, from Latin gibbus, hump.]

gib′bous·ly adv.
gib′bous·ness n.


(ˈɡɪbəs) or


1. (Astronomy) (of the moon or a planet) more than half but less than fully illuminated
2. having a hunchback; hunchbacked
3. bulging
[C17: from Late Latin gibbōsus humpbacked, from Latin gibba hump]
ˈgibbously adv
ˈgibbousness n


(ˈgɪb əs)

1. (of a heavenly body) convex at both edges, as the moon when more than half full.
2. humpbacked.
[1350–1400; Middle English < Latin gibbōsus humped =gibb(a) hump + -ōsus -ous]
gib′bous•ly, adv.
gib′bous•ness, n.


More than half but less than fully illuminated. Used to describe the moon or a planet. Compare crescent.
ThesaurusAntonymsRelated WordsSynonymsLegend:
Adj.1.gibbous - characteristic of or suffering from kyphosis, an abnormality of the vertebral column
unfit - not in good physical or mental condition; out of condition; "fat and very unfit"; "certified as unfit for army service"; "drunk and unfit for service"
2.gibbous - (used of the moon) more than half full
bulging, convex - curving or bulging outward


adj moonDreiviertel-
References in classic literature ?
She became more sociable, and I was beginning to be very happy; but, on coming within sight of the grim old hall, she stood still, and turned towards me while she spoke, as if expecting I should go no further, that the conversation would end here, and I should now take leave and depart - as, indeed, it was time to do, for 'the clear, cold eve' was fast 'declining,' the sun had set, and the gibbous moon was visibly brightening in the pale grey sky; but a feeling almost of compassion riveted me to the spot.
As I stood there musing over this too perfect triumph of man, the full moon, yellow and gibbous, came up out of an overflow of silver light in the north-east.
7 DAWN: It gets crowded above the Teapot in Sagittarius as the waning gibbous Moon floats some 1 1/2[degrees] above Saturn and a little more than 4[degrees] above and right of Mars.
However, Ms Wibisono said moonlight from the waning gibbous moon - a phase where the Earth's natural satellite is partially illuminated by direct sunlight - might make it harder to spot the fainter meteors.
As of Monday the moon was a waxing gibbous, meaning it was still getting brighter.
4 Crescent, gibbous, new and full are phases of what?
On the big Perseid night of August 11-12, a waxing gibbous Moon won't set until around 1 a.
Russki accent, pointing out a spectacular waxing gibbous emerging from a
Observation of the large gibbous phase at the start of this elongation will be favourable, as early indications from 2013 May onwards have already shown, but when the planet reaches greatest elongation on 2013 Nov 1 it will be in extreme south declination.
The doodle also shows all phases of the moon, full, half, crescent and gibbous, as it moves across the sky.
With: Tatyana Ali, Lyriq Bent, Stephan James, Fefe Dobson, Richard Chevolleau, CCH Pounder, Paul Campbell, Kadeem Wilson, Brian Brown, Grace Aberdeen, Shaun Austin-Olsen, Teri-Leigh Bovell, Peter Bryant, Eugene Clark, Jess Gibbous.