From WordNet (r) 2.0 (August 2003) [wn]:
avenue
n 1: a line of approach; "they explored every avenue they could
think of"; "it promises to open new avenues to
understanding"
2: a wide street or thoroughfare [syn: boulevard]
From The Collaborative International Dictionary of English v.0.48 [gcide]:
Avenue \Av"e*nue\, n. [F. avenue, fr. avenir to come to, L.
advenire. See Advene.]
1. A way or opening for entrance into a place; a passage by
which a place may by reached; a way of approach or of
exit. "The avenues leading to the city by land."
--Macaulay.
[1913 Webster]
On every side were expanding new avenues of inquiry.
--Milman.
[1913 Webster]
2. The principal walk or approach to a house which is
withdrawn from the road, especially, such approach
bordered on each side by trees; any broad passageway thus
bordered.
[1913 Webster]
An avenue of tall elms and branching chestnuts. --W.
Black.
[1913 Webster]
3. A broad street; as, the Fifth Avenue in New York.
[1913 Webster]