Rill
Rill (ril) , noun
[Compare LG. rille a small channel or brook, a furrow, a chamfer, Old English rigol a small brook, French rigole a trench or furrow for water, Welsh rhill a row, rhigol a little ditch. r11.]
1.
A very small brook; a streamlet.
2.
(Astronomy) See Rille.
Rill , intransitive verb
To run a small stream. [Rare] — Prior