Webster's Revised Unabridged Dictionary (1913)
An underground way or gallery; especially, a passage under a street, in which water mains, gas mains, telegraph wires, etc., are conducted.
Webster's Revised Unabridged Dictionary (1913), edited by Noah Porter. About
hEnglish - advanced version
succeed \suc*ceed"\ (?), v. t. [imp. & p. p. succeeded; p. pr. & vb. n. succeeding.] [l. succedere, successum; sub under + cedere to go, to go along, approach, follow, succeed: cf. f. succéder. see cede, and cf. success.]
1. to follow in order; to come next after; hence, to take the place of; as, the king's eldest son succeeds his father on the throne; autumn succeeds summer. as he saw him nigh succeed.
2. to fall heir to; to inherit. [obs. & r.]
3. to come after; to be subsequent or consequent to; to follow; to pursue. destructive effects succeeded the curse. t. browne.
4. to support; to prosper; to promote. [r.] succeed my wish and second my design.
BTS Transportation Expressions
1) That portion of a transportation system that is constructed beneath the ground surface, regardless of its method of construction. 2) An underground rail rapid transit system or the tunnel through which it runs. 3) In local usage, sometimes used for the entire rail rapid transit system, even if it is not all beneath the ground surface. 4) A pedestrian underpass. (TRB1)
Rail transit way below surface with a cover over the tunnel. Cut and cover, bored tunnel, underwater tubes, etc., are included. (FTA1)
By the Bureau of Transportation Statistics