(tunnels, tunnelling, tunnelled)
Frequency: The word is one of the 3000 most common words in English.
Note: in AM, use 'tunneling', 'tunneled'
1.
A tunnel is a long passage which has been made under the ground, usually through a hill or under the sea.
...two new railway tunnels through the Alps.
N-COUNT: oft supp N
2.
To tunnel somewhere means to make a tunnel there.
The rebels tunnelled out of a maximum security jail...
VERB: V prep/adv
3.