Lengua inglesa
1 a constructed underground passage through or under some obstruction, eg a hill, river, road, etc, allowing access for pedestrians, vehicles, trains, etc.
2 an underground passage that a burrowing animal, such as a mole, digs, often one of a connected series.
verb (tunnelled , tunnelling ; US tunneled , tunneling )
1 intr (often tunnel through, under, etc ) to make a tunnel through, under, etc (a hill, river, road, etc).
2 to make (a tunnel or passageway) through, under, etc a hill, river, road, etc.
3 (tunnel one's way) to make one's way by digging a tunnel.
[15c: from French tonel cask]
tunneller noun .
tunnelling adjective , noun .
the light at the end of the tunnel see under light.

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