зацепление

см. тж. находиться в зацеплении

When gears (inter)mesh, one pair of teeth must remain in engagement until the following pair are in a position to carry the load.

The meshing of a pair of huge cogwheels ...

The engagement of the sprocket and chain must be smooth.

Источник: Русско-английский научно-технический словарь на Gufo.me