• noun:   a knowledge domain that you are interested in or are communicating about

  Example: "It was a limited domain of discourse"

• noun:   territory over which rule or control is exercised

  Example: "His domain extended into Europe"

• noun:   the set of values of the independent variable for which a function is defined
• noun:   people in general; especially a distinctive group of people with some shared interest
• noun:   a particular environment or walk of life

Related words...