Noun

(en noun)

A small brook or stream; a streamlet.

* (Charles Cotton) (1630-1687)

Rills running down the steepest slopes develop into rivulets .

*, chapter=23

, title= The Mirror and the Lamp , passage=The struggle with ways and means had recommenced, more difficult now a hundredfold than it had been before, because of their increasing needs. Their income disappeared as a little rivulet that is swallowed by the thirsty ground.}}

Noun

(wikipedia rill) (en noun)

A very small brook; a streamlet.

* 1797 , :

So twice five miles of fertile ground

With walls and towers were girdled round:

And there were gardens bright with sinuous rills ,

Where blossomed many an incense-bearing tree;

And here were forests ancient as the hills,

Enfolding sunny spots of greenery.

(planetology)