tun·nel (tŭn'əl)
n.

1. An underground or underwater passage.
2. A passage through or under a barrier.
3. Obsolete. The main flue on a chimney.

v., -neled, or -nelled, -nel·ing, or -nel·ling, -nels, or -nels.

v.tr.

1. To make a tunnel through or under.
2. To produce, shape, or dig in the form of a tunnel.

v.intr.
To make a tunnel.

[Middle English tonel, tubular net, from Old French tonnelle, diminutive of tonne, tun, possibly of Celtic origin.]

tunneler tun'nel·er or tun'nel·ler n.

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The American Heritage® Dictionary of the English Language, Fourth Edition Copyright © 2007, 2000 by Houghton Mifflin Company. Updated in 2009. Published by Houghton Mifflin Company. All rights reserved.

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