furrow

Short definition from Wiktionary

Noun

1. 1
   A trench cut in the soil, as when plowed in order to plant a crop.
2. 2
   Any trench, channel, or groove, as in wood or metal.
3. 3
   A deep wrinkle in the skin of the face, especially on the forehead.

Verb

1. 1
   To cut one or more grooves in (the ground, etc.).
2. 2
   To wrinkle.
3. 3
   To pull one's brows or eyebrows together due to concentration, worry, etc.
4. 4
   to become furrowed

Proper noun

1. 1
   A surname.