Meaning: Area of expertise or knowledge
* The scientist's domain was astrophysics, but he was also fascinated by biology.
* I'm not familiar with the domain of quantum physics, but I'm willing to learn.
Meaning: Area of control or responsibility
* The CEO has a wide domain of influence in the company.
* The local government is responsible for the domain of public safety.
Meaning: A website's address
* The domain name for my website is "www.example.com."
* I need to register a domain name for my new online business.
Meaning: A set of values for which a function is defined
* The function is defined for all values in the domain of real numbers.
* The domain of the function is restricted to positive integers.
You can also use "domain" figuratively to refer to a specific area of experience or activity. For example:
* He's a master in the domain of fine dining.
* The domain of the internet is vast and constantly evolving.