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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.
American Heritage® Dictionary of the English Language, Fifth Edition. Copyright © 2016 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.


(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
Collins English Dictionary – Complete and Unabridged, 12th Edition 2014 © HarperCollins Publishers 1991, 1994, 1998, 2000, 2003, 2006, 2007, 2009, 2011, 2014


(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.
Random House Kernerman Webster's College Dictionary, © 2010 K Dictionaries Ltd. Copyright 2005, 1997, 1991 by Random House, Inc. All rights reserved.


More than half but less than fully illuminated. Used to describe the moon or a planet. Compare crescent.
The American Heritage® Student Science Dictionary, Second Edition. Copyright © 2014 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.
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
Based on WordNet 3.0, Farlex clipart collection. © 2003-2012 Princeton University, Farlex Inc.


adj moonDreiviertel-
Collins German Dictionary – Complete and Unabridged 7th Edition 2005. © William Collins Sons & Co. Ltd. 1980 © HarperCollins Publishers 1991, 1997, 1999, 2004, 2005, 2007
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.
The fat gibbous moon hovers to the right of Saturn on the 11th and to its left on the 12th.
From June 18 to 19, the planet will rise with the waning gibbous phase of the Moon.
The moon photo, "Waxing Gibbous" comes from Marc Jolas Aquino.
NASA explained: "Using precise timing, the Earth-orbiting space platform was photographed in front of a partially lit gibbous Moon last month."
[24-25] ALL NIGHT: The waning gibbous Moon starts the evening around 1/2[degrees] from the Beehive Cluster (M44) in Cancer; by sunrise, the Moon has increased the separation to 4[degrees].
Her radiant gibbous moon looks to dangers far past the harbored masts of Rotterdam, or the glistening fields around Delft.
Moon -- Ahmed Waheed CAIRO -- 21 July 2018: The Waning Gibbous Moon is near Jupiter, in a phenomenon that can be observed with the naked eye in the skies of the Arab region, according to Jeddah Astronomy Society Saturday.
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.
4 Crescent, gibbous, new and full are phases of what?