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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 ?
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.
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.
20) From this finding, a reasonable worst-case observing scenario was chosen--specifically, from the Diego Garcia GEODSS site with a minimum viewing angle of 33[degrees] elevation with a gibbous moon 45[degrees] from the sight line.
There was a bright gibbous moon and a billion stars overhead.
Which is why Pete and I have enjoyed so many full-blown domestics, usually triggered by the alignment of a gibbous moon and Saturn, at precisely the point where, having been asked the daily question, he has said "I don't mind", "you choose" or (the Semtex of all responses) "I can't think what I want for dinner while I'm having breakfast".
Your seats bear the gibbous imprint of your own buttocks; the upholstery absorbs your bodily odors; the metalwork bears witness via dents and dings and distresses to your recklessness or bad luck.
Implementing agency : Eastern School District Elementary School, Incheon, Incheon gibbous
31) Gibbous deformity of the spine, commonly seen in tuberculosis, is an unusual finding in coccidioidomycosis.
The phase of an outer planet is always full or gibbous (more than half but not all of the disc illuminated); the gibbous phase is quite pronounced on Mars, but less so on the more distant planets.
Eye of toad, tongue of newt, take at midnight by the light of a waning gibbous moon while swinging a black moggie by its tail.
However, there are possibilities that the bright moon, also called as waning gibbous moon, will wash out some Lyrid meteors this year.
Unfortunately the Moon will spoil the party to some extent this year, as on the night of maximum it is waxing gibbous in nearby Taurus.