- A boxer is a person who fights with their fists in the often violent sport of boxing. (See also list of boxers, women's boxing)
- Boxers are a breed dog. See Boxer (dog)
- Boxer is a text editor for MS-DOS and Microsoft Windows.
- Boxers were members of a powerful Chinese organization which committed numerous acts of violence on Europeans and Christian converts in the Boxer Rebellion against foreigners in 1900.
- A boxer short is a kind of undergarment.
- Several US Navy ships are named USS Boxer.