To cut one or more grooves in (the ground, etc.).
To wrinkle.
To pull one's brows or eyebrows together due to concentration, worry, etc.
A trench cut in the soil, as when plowed in order to plant a crop.
Any trench, channel, or groove, as in wood or metal.
A deep wrinkle in the skin of the face, especially on the forehead.
To fold or pleat (usually used in passive).
Folded multiple times lengthwise like a fan, usually lending stiffness to a flat structure such as a leaf; corrugated; pleated.