■ noun
1》 an artificial underground passage, as built through a hill or under a building or by a burrowing animal.
2》 a poly~.
■ verb ( ~s , ~ling , ~led ; US ~s , ~ing , ~ed )
1》 dig or force a passage underground or through something.
2》 Physics (of a particle) pass through a potential barrier.
Derivatives
~ler noun
Origin
ME (in the senses '~-shaped net' and 'flue of a chimney'): from OFr. tonel , dimin. of tonne 'cask'.