This is the 17481st most frequent Russian word.
тоннель
Tunnel.
Here, 'тоннель' is used to refer to a physical structure that allows passage under or through an obstacle.
Мы прошли через тоннель, чтобы сократить путь.
We went through the tunnel to shorten the route.
Here, 'тоннель' is used metaphorically to describe a narrowed perspective or mind status.
Психологический тоннель может ограничивать видение человека.
A psychological tunnel can restrict a person's vision.
In this example, 'тоннель' is part of a compound term describing a hypothetical tool/concept in science fiction.