Home Diabetes Glossary bunion bunion Wednesday,January 4, 2023 ByDiabetesCare.net by DiabetesCare.net | Jan 4, 2023 | 0 comments (BUN-yun): a bulge on the first joint of the big toe, caused by the swelling of a fluid sac under the skin. This spot can become red, sore, and infected. Submit a Comment Cancel replyYou must be logged in to post a comment.