Word of the Day : February 16, 2019


adjective JIB-us


1 a : 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.


The fresh layer of snow glistened under the light of the waxing gibbous moon.

"During the fourth lunar orbit, Anders was engaged in photographing the lunar surface when he noticed a slightly gibbous Earth rising above the surface as the spacecraft passed over from the moon's far side to its near side." — Alan Hale, The Alamogordo (New Mexico) Daily News, 23 Dec. 2018

Test Your Vocabulary

What Greek goddess's name (beginning with "C") is used to refer to the moon in literary personification?



More Words of the Day

Love words? Need even more definitions?

Subscribe to America's largest dictionary and get thousands more definitions and advanced search—ad free!