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.]
(..) I'll be with you in a second. Give me a few minutes. Thank you. You guys get lost. I don't want to see you. - Is everyone in position? - This has to look natural. - No women, no kids. Right? - Right. Jogger in the yellow and orange? Keep calm. Don't take your eyes off him. (..)1994 Léon: The Professional