From WordNet (r) 3.0 (2006) [wn]:
bypass
n 1: a highway that encircles an urban area so that traffic does
not have to pass through the center [syn: beltway,
bypass, ring road, ringway]
2: a surgically created shunt (usually around a damaged part)
3: a conductor having low resistance in parallel with another
device to divert a fraction of the current [syn: shunt,
electrical shunt, bypass]
v 1: avoid something unpleasant or laborious; "You cannot bypass
these rules!" [syn: bypass, short-circuit, go around,
get around]
From The Collaborative International Dictionary of English v.0.48 [gcide]:
By-pass \By"-pass\, n. (Mech.)
A by-passage, for a pipe, or other channel, to divert
circulation from the usual course.
[1913 Webster]