Word of the Day:

October 3, 2025

gibbous

adjective JIB-us

What it Means

Gibbous is most often used to describe the moon or a planet when it is seen with more than half but not all of the apparent disk illuminated.

// The waxing gibbous moon provided the perfect lighting for a night of spooky storytelling around the campfire.

See the entry

Gibbous in Context

“At 3:30 a.m. the gibbous moon is high in the south and Perseus is nearly overhead. Set up a comfortable lawn chair facing away from any bright lights, ideally looking toward the northeast with the moon to your back. Have insect repellent handy along with hot chocolate, tea or coffee and enjoy the show.” — Tim Hunter, The Arizona Daily Star, 7 Aug. 2025

More example sentences

Test Your Vocabulary with M-W Games & Quizzes

QUIZ Word Builder Quiz Vol. 2 Pick the letter that when added to a word will make a new word. Rinse and repeat.

QUIZ Wordmaxxing Slang Quiz Give your vocabulary a glow up by getting sendy with these questions about slang.

Latest Quizzes

Did You Know?

The adjective gibbous has its origins in the Latin noun gibbus, meaning “hump.” It was adopted into Middle English to describe rounded, convex things. While it has been used to describe the rounded body parts of humans and animals (such as the back of a camel) and to describe the shape of certain flowers (such as snapdragons), the term is most often used to describe the moon: a gibbous moon is one that is between half full and full.

Quiz

What is the name, starting with S, of the Greek goddess of the moon?

View the Answer