The term "underarm" typically refers to the outer surface of the axilla. However, the terms are sometimes used interchangeably in casual contexts. Colloquially, armpit refers to the hollow beneath the junction of the arm and shoulder.
In some modern Western cultures, it is common for women to remove underarm hair. Some view this practice as an aesthetic matter, while others consider it to be a cultural product of patriarchy. As underarm hair grows quickly, shaving must be performed frequently, or else stubble will appear in the axilla.
Throughout the feminist movement, previously in the hippie culture, and in some areas of the punk rock scene, some women choose to keep their underarm hair for a variety of reasons, from subversion to egalitarianism to comfort. Conversely, some men choose to remove their underarm hair for similar aesthetic reasons or to reduce friction in some sports, such as swimming.