A suit may refer to any of the following:
When referring to something that is worn, a suit is an outfit, usually made of all the same fabric. Suits are often complimented by a matching jacket, trousers, or skirt.
When referring to an outfit worn in a clean room a suit is another name for a bunny suit.
Suit is a common misspelling for Suite when taking about a collection of software or programs, for example, a software suite or Microsoft Office suite.