The buttocks or "gluteus maximus" (sometimes just "glutes") are the two masses of muscle and fat covering the posterior aspect of the human (primate) pelvis. They allow humans (primates) to sit upright comfortably without resting weight on their feet, as (for example) cats and dogs do when they sit upright.

They belong to the intimate parts. Exposing the bare buttocks as a protest or for fun is called mooning.

In many cultures, corporal punishment is traditionally delivered on the buttocks. This is especially true for lighter punishment and domestic discipline. Different reasons have been put forward to explain this:

  • The buttocks are usually not exposed, making the punishment invisible to outsiders (and therefore making it difficult to prosecute cases of severe beating).
  • While there are many nerve endings in the area (ensuring substantial pain), there is relatively little risk of the victim sustaining long-term injury since internal organs are unlikely to be affected.
  • Some critics of corporal punishment see it as merely a sexual fetish, pointing to the well-documented spanking fetish as evidence.