- to make different in some particular, as size, style, course, or the like; modify: to alter a coat; to alter a will; to alter course.
- to castrate or spay.
- to change; become different or modified.
- U.S. physicist.
- alteration.
- to make or become different in some respect; change
- (tr) informal, mainly US a euphemistic word for castrate, spay
