Tunnelling

noun
1.
an underground passage.
2.
a passageway, as for trains or automobiles, through or under an obstruction, as a city, mountain, river, harbor, or the like.
3.
an approximately horizontal gallery or corridor in a mine.
4.
the burrow of an animal.
5.
Dialect. a funnel.
verb (used with object), tunneled, tunneling or (especially British) tunnelled, tunnelling.
6.
to construct a passageway through or under:
to tunnel a mountain.
7.
to make or excavate (a tunnel or underground passage):
to tunnel a passage under a river.
8.
to move or proceed by or as if by boring a tunnel:
The river tunneled its way through the mountain.
9.
to pierce or hollow out, as with tunnels.
verb (used without object), tunneled, tunneling or (especially British) tunnelled, tunnelling.
10.
to make a tunnel or tunnels:
to tunnel through the Alps.
noun
1.
an underground passageway, esp one for trains or cars that passes under a mountain, river, or a congested urban area
2.
any passage or channel through or under something
3.
a dialect word for funnel
4.
(obsolete) the flue of a chimney
verb -nels, -nelling, -nelled (US) -nels, -neling, -neled
5.
(transitive) to make or force (a way) through or under (something): to tunnel a hole in the wall, to tunnel the cliff
6.
(intransitive; foll by through, under, etc) to make or force a way (through or under something): he tunnelled through the bracken

tunnel tun·nel (tŭn’əl)
n.
A passage located through or under a barrier.
tunes
networking
(US: “tunneling”) Encapsulation of protocol A within protocol B, such that A treats B as though it were a data link layer. Tunnelling is used to get data between administrative domains which use a protocol that is not supported by the internet connecting those domains.
(1997-03-26)
see: light at the end of the tunnel