Real Dictionary

bypass
A bypass is a surgical operation performed on or near the heart, in which the flow of blood is redirected so that it does not flow through a part of the heart which is diseased or blocked.
verb: If you bypass someone or something that you would normally have to get involved with, you ignore them, often because you want to achieve something more quickly.

bypass in American English
a way, path, etc. between two points that avoids or is auxiliary to the main way; specif., an alternative highway route, as for skirting an urban area
to go around instead of through; use a bypass to avoid
noun: a road enabling motorists to avoid a city or other heavy traffic points or to drive around an obstruction

bypass in British English
noun: a main road built to avoid a city or other congested area
verb: to go around or avoid (a city, obstruction, problem, etc)

bypass in Mechanical Engineering
noun: A bypass is a way of diverting a flow of fluid around a system.