Definition of tunnel
(Entry 1 of 2)
tunnel
verbDefinition of tunnel (Entry 2 of 2)
1
: to make or use a tunnel
2
physics
: to pass through a potential barrier
electrons tunneling through an insulator between semiconductors
: to make a tunnel or similar opening through or under
also
: to make (one's way) by or as if by making a tunnel
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Merriam-Webster unabridged
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Time Traveler for tunnel
The first known use of tunnel was in 1508
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