gibbous
UK[ˈɡɪbəs]US[ˈɡɪbəs]
adj
(of the moon or a planet) having the illuminated part greater than a semicircle and less than a circle.
adj
convex or protuberant.
Etymology
the word "gibbous" entered english in the late 14th century from the latin word "gibbosus," meaning "humped" or "crooked." this latin term itself derives from "gibbus," a noun meaning "hump." the ultimate origin is likely the proto-indo-european root geibh-, conveying a sense of being bent or curved. the semantic journey is direct, from the physical concept of a rounded protuberance to its specific astronomical application describing the swollen, convex shape of the moon between half and full, and more generally to any rounded bulge.
Analysis
the word is a simplex form derived as a whole from latin.
Examples
a gibbous moon hung brightly in the night sky.
the old man had a gibbous back from years of labor.
the gibbous shape of the lens helped to focus the light.