It is dug through surrounding soil, earth or rock, or laid under water, and is usually completely enclosed except for the two portals common at each end, though there may be access and ventilation …

Dec 19, 2025 · Tunnels and underground excavations, horizontal underground passageway produced by excavation or occasionally by nature’s action in dissolving a soluble rock. Tunnels have many …

The meaning of TUNNEL is a covered passageway; specifically : a horizontal passageway through or under an obstruction. How to use tunnel in a sentence.

TUNNEL definition: an underground passage. See examples of tunnel used in a sentence.

TUNNEL definition: 1. a long passage under or through the ground, especially one made by people: 2. the long passage…. Learn more.

Define tunnel. tunnel synonyms, tunnel pronunciation, tunnel translation, English dictionary definition of tunnel. n. 1. An underground or underwater passage. 2. A passage through or under a barrier such …

Dec 15, 2025 · (mining) A level passage driven across the measures, or at right angles to veins which it is desired to reach; distinguished from the drift, or gangway, which is led along the vein when …

Definition of tunnel noun in Oxford Advanced American Dictionary. Meaning, pronunciation, picture, example sentences, grammar, usage notes, synonyms and more.

Today, engineers know that there are three basic steps to building a stable tunnel. The first step is excavation: engineers dig through the earth with a reliable tool or technique. The second...

Tunnels are dug in types of materials varying from soft clay to hard rock.