The definition of gibbous refers to a moon in between a half-moon but less than a full moon, or something that protrudes or creates an obvious bulge.(adjective)
See gibbous in Webster's New World College Dictionary
Origin: ME < L gibbosus < gibba: see gib
See gibbous in American Heritage Dictionary 4
Origin: Middle English, bulging
Origin: , from Late Latin gibbōsus, hunch-backed
Origin: , from Latin gibbus, hump.
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