butt

Buttocks, commonly referred to as the butt or buttocks, are the pair of rounded portions of the anatomy located on the posterior aspect of the pelvis. Each side consists of skin, fat, and the gluteal muscles, most notably the gluteus maximus, medius, and minimus. The buttocks lie on either side of the intergluteal cleft and are involved in movement and posture. The gluteus maximus is the largest muscle and helps extend and externally rotate the hip, while the gluteus medius and minimus stabilize the pelvis during walking and running. The buttocks also provide cushioning and bear weight when seated.

Fat distribution in the buttocks varies by sex, age, body composition, and fitness. The appearance and size of the buttocks can change with strength training focused on the gluteal muscles or with changes in body fat. Common health-related concerns include muscular imbalances, strain injuries, or soreness from activity, as well as conditions such as cellulite or piriformis-related discomfort. Maintaining proper posture, gradual strength training, and balanced conditioning help preserve function and reduce injury risk.

Other uses of the word butt include a cigarette butt, the end portion of a cigarette, and butt joints in carpentry, where two pieces are joined at ends. The term also appears in idioms such as to butt heads, meaning to clash or argue. In everyday language, context usually determines which meaning is intended.