The term virtual is a concept applied in many fields with somewhat differing connotations, and also, differing denotations. Colloquially, 'virtual' has a similar meaning to ' quasi ...
http://en.wikipedia.org/wiki/Virtual

In object-oriented programming (OOP), a virtual function or virtual method is a function whose behavior, by virtue of being declared "virtual," is determined by the definition of a ...
http://en.wikipedia.org/wiki/Virtual_functions

Virtual Access provide high quality casual, permanent dial, ADSL and ISDN Internet access throughout Australia. Virtual Access also provides high uptime hosting services with rapid ...
http://www.virtual.net.au/

adjective . 1. being such in power, force, or effect, though not actually or expressly such: a virtual dependence on charity.
http://dictionary.reference.com/search?q=virtual&r=66

Virtual-USAairways - Forget the Rest, Come Fly for the Best!
http://www.virtual-usaairways.com/