A multi-homed device contains multiple network adapters. Multi-homed computers are often used as proxy servers, firewalls, and other types of gateways. A proxy server often has one adapter with an external Web address (asssigned by an ISP) and another adapter to use a private intranet address (such as 192.168.0.1).
Some Web servers like Apache support a feature called virtual hosting. Virtual hosting allows a computer to act as if it possesses multiple IP addresses. Virtual hosting is not the same as multi-homing, that refers to multiple network interfaces of a device.