rut

A sunken track or groove made by the passage of vehicles.

An uninspired routine or pattern of behavior that one continues unthinkingly or because change is difficult.

To make ruts in (a path, for example).

A regularly recurring condition of fertility during which breeding occurs in certain mammals, especially deer and various other ungulates.

The period during which this condition occurs.

To be in rut.

A narrow track worn or cut in the ground; especially, the hollow track made by a wheel in passing over the ground.

A wrinkle.

Any beaten path or mode of procedure; an established habit or course.

To mark with or as with ruts; trace furrows in; also, to wrinkle: as, to rut the earth with a spade, or with cart-wheels.