Here's my attempt to describe vetiver, perhaps this will help. Complex, sometimes grassy, sometimes earthy. Can have a certain comforting quality like a warm cushion. Somewhere between "green" and "brown" in tone. It can have a rootsy quality, with a hint of sweetness.
Vetiver is used in many scents. If you smell Lalique's Encre Noir or Guerlain's Vetiver you will see examples. Jo Malone Vetiver is a good example of a basic vetiver smell. So too is Givenchy Vetiver but that is harder to find.
Vetiver essential oil is very powerful and may not be particularly pleasant in and of itself. But a tiny bit in perfume can be marvelous.