gibbous

adjective
gib·​bous | \ ˈji-bəs How to pronounce gibbous (audio) , ˈgi- How to pronounce gibbous (audio) \

Definition of gibbous

1a : marked by convexity or swelling
b of the moon or a planet : seen with more than half but not all of the apparent disk illuminated
2 : having a hump : humpbacked

Did you know?

The adjective gibbous has its origins in the Latin noun gibbus, meaning "hump," and in the Late Latin adjective gibbosus, meaning "humpbacked," which Middle English adopted in the 14th century as gibbous. Gibbous has been used to describe the rounded body parts of humans and animals (such as the back of a camel) or to describe the shape of certain flowers (such as snapdragons). The term is most often identified, however, with the study of astronomy. A gibbous moon is one that is more than a half-moon but less than full.

Examples of gibbous in a Sentence

Recent Examples on the Web Through binoculars or a telescope, a small gibbous appears: a mostly full Venus. Ethan Siegel, Forbes, 6 Sep. 2021 This year’s peak will take place under an unfavorable gibbous moon, but the shower should be strong enough for sky watchers to see some meteors. oregonlive, 2 Jan. 2022 However, the waning gibbous Moon—tonight 98%-lit—will blot-out all but the very brightest bits of the great comet. Jamie Carter, Forbes, 17 Oct. 2021 However, the waning gibbous Moon—tonight 98%-lit—will blot-out all but the very brightest bits of the great comet. Jamie Carter, Forbes, 17 Oct. 2021 The moon is unfortunately in a waxing gibbous phase on peak night, meaning that much of the moon will be visible. Megan Marples, CNN, 16 Nov. 2021 However, the waning gibbous Moon—tonight 98%-lit—will blot-out all but the very brightest bits of the great comet. Jamie Carter, Forbes, 17 Oct. 2021 However, the waning gibbous Moon—tonight 98%-lit—will blot-out all but the very brightest bits of the great comet. Jamie Carter, Forbes, 17 Oct. 2021 However, the waning gibbous Moon—tonight 98%-lit—will blot-out all but the very brightest bits of the great comet. Jamie Carter, Forbes, 17 Oct. 2021 See More

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'gibbous.' Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. Send us feedback.

First Known Use of gibbous

14th century, in the meaning defined at sense 1a

History and Etymology for gibbous

Middle English, from Late Latin gibbosus humpbacked, from Latin gibbus hump

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Dictionary Entries Near gibbous

gibbosity

gibbous

Gibbs

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Cite this Entry

“Gibbous.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/gibbous. Accessed 20 May. 2022.

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More Definitions for gibbous

gibbous

adjective
gib·​bous | \ ˈjib-əs How to pronounce gibbous (audio) , ˈgib- How to pronounce gibbous (audio) \

Medical Definition of gibbous

1 : marked by swelling or convexity especially on one side : protuberant
2 : having a hump

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