striation

Short definition from Wiktionary

Noun

1. 1
   One of a number of parallel grooves and ridges in a rock or rocky deposit, formed by repeated twinning or cleaving of crystals.
2. 2
   One of a number of parallel scratch lines in rock outcrops, formed when glaciers dragged rocks across the landscape.
3. 3
   The action of marking with a stria.
4. 4
   The result of being marked with a stria.
5. 5
   a parallel series of small grooves, channels, or impressions typically within a metal roof panel used to help reduce the potential for oil-canning.