He died of 'natural causes'. [=he died because he was ill or old and not by being killed in an accident, battle, etc.]
She was adopted immediately after she was born and never knew her 'natural' [=(more commonly) 'birth'] parents.
a country rich in 'natural resources' [=a country that has many valuable plants, animals, minerals, etc.]
(..) And that's a good thing? He was the most experienced commander in Westeros. He chose this place for a reason. Those mountains are a natural fortification. There's a stream down there for the horses. We're not staying here long. Another storm could hit any day. Aye, the snows defeated Stannis (..)2016 TvShow: Game of Thrones Title: The Broken Man Season: 6 Episode 7