Domain may refer to:
Domain (taxonomy), a taxonomic subdivision larger than a kingdom
Domain name, the name of a realm of administrative autonomy, authority, or control on the Internet
Magnetic domain (physics), a region within a magnetic material which has uniform magnetization
High-field domain (physics) in semiconductors, also called Böer domain
Protein domain (biology), a part of a protein that can exist independently of the rest of the protein chain
Territory (subdivision), a non-sovereign geographic area which has come under the authority of another government
Demesne, in English common law and other Medieval European contexts, lands directly managed by their holder rather than being delegated to subordinate managers
Domain Group, one of the two major real estate marketing portals in Australia
The domain of discourse in logic is the collection of entities of interest in logical analysis
Domain (sociolinguistics), the situations in which a language is used, for instance, in formal education, at home, or by a government.