rill

Multiple Entries:
  rill    rille  

Concise Oxford English Dictionary © 2008 Oxford University Press:
rill /rɪl/

▶noun

• 1 a small stream.

• 2 a shallow channel cut in soil or rocks by running water. ■variant spelling of rille.

– origin C16: prob. of Low Ger. origin.

Concise Oxford English Dictionary © 2008 Oxford University Press:
rille /rɪl/ (also rill)

▶noun Astronomy a fissure or narrow channel on the moon's surface.

– origin C19: from Ger. (see rill).