1. Humpbacked.

2. Protuberant; convex, as the moon during the week before and after full moon; humpbacked.

Nuttall's Standard dictionary of the English language By Nuttall, P.Austin

• gibb's,
• ginious,
• quibbous,
• gilbulus,
• gibbosse,
• gibbos,
• vibbous,
• bibbous,
• hibbous,
• yibbous,
• tibbous,
• gigbous,
• gibous,
• gibbousnes,
• gibboom,
• gibfihs,
• gipooun,
• Glubous,
• globbous,
• gobioud

• gibbose,
• gibbon,
• gibbs.

The adjective form of the word "gibbous" is "gibbous".

The plural form of the word "gibbous" is "gibbous".

The singular form of the word "gibbous" is "gibbosity"