- noun the main controlling computer in a multi-user or distributed system
- noun a computer used to write and debug software for another computer, often using a cross compiler
- noun a computer in a network that provides special services or programming languages to all users
- Within a network, a computer that provides users with services such as access to other computers and/or databases, and which may also perform control functions. Over the Internet, for instance, a host computer may be accessed by a user from a remote location who seeks access to information, email services, and so on.
- Any computer connected to a network, such as a TCP/IP network.