a field of action, thought, influence, etc.

the domain of science.

the territory governed by a single ruler or government; realm.

a realm or range of personal knowledge, responsibility, etc.

a region characterized by a specific feature, type of growth or wildlife, etc.

We entered the domain of the pine trees.

Law . land to which there is superior title and absolute ownership.

Mathematics .

the set of values assigned to the independent variables of a function.

region ( def. 11a ) .

Computers .

a group of computers and devices on a network that are administered under the same protocol.

the top level in a domain name, indicating the type of organization, geographical location, or both, and officially designated in the suffix, as .com for commercial enterprises in the U.S.

Physics . one of many regions of magnetic polarity within a ferromagnetic body, each consisting of a number of atoms having a common polarity, and collectively determining the magnetic properties of the body by their arrangement.

Crystallography . a connected region with uniform polarization in a twinned ferroelectric crystal.

noun

authority , bailiwick , concern , demesne , department , discipline , district , dominion , empire , estate , field , home park , jurisdiction , land , neck of the woods , occupation , orbit * , power , province , quarter , realm , region , scope , slot , specialty , sphere , stomping grounds , terrain , territory , turf , walk , wing , arena , circle , orbit , scene , subject , world , area , arrondissement , dominance , domination , kingdom , principality , property , sovereignty , supremacy , suzerainty , transcendency