n. & v.
--n.
1. an artificial underground passage through a hill or under a road or river etc., esp. for a railway or road to pass through, or in a mine.
2 an underground passage dug by a burrowing animal.
3 a prolonged period of difficulty or suffering (esp. in metaphors, e.g. the end of the tunnel).
4 a tube containing a propeller shaft etc.
--v. (tunnelled, tunnelling; US tunneled, tunneling)
1. intr. (foll. by through, into, etc.) make a tunnel through (a hill etc.).
2 tr. make (one's way) by tunnelling.
3 intr. Physics pass through a potential barrier.
Phrases and idioms:
tunnel diode Electronics a two-terminal semiconductor diode using tunnelling electrons to perform high-speed switching operations. tunnel-kiln a kiln in which ceramic ware is carried on trucks along a continuously-heated passage. tunnel-net a fishing-net wide at the mouth and narrow at the other end. tunnel vision
1. vision that is defective in not adequately including objects away from the centre of the field of view.
2 colloq. inability to grasp the wider implications of a situation.
Derivatives:
tunneller n.
Etymology: ME f. OF tonel dimin. of tonne TUN