Characterized by convexity; protuberant. / (astronomy, of a celestial body) Having more than half (but not the whole) of its disc illuminated. / Humpbacked.

(astronomy) More than half full in phase, but growing smaller.

(astronomy) A lunar phase either side of the full moon when the moon's disc as seen from the Earth is larger than a semicircle.

plural of gibbous moon

In a gibbous manner.

The state or quality of being gibbous.