Die out and Thin out

Die out verb - Become extinct.

Thin out and die out are semantically related in decrease topic. In some cases you can use "Thin out" instead a verb "Die out", when it comes to topics like decrease to a point.

Thin out verb - Make sparse.

Die out and thin out are semantically related in decrease topic. Sometimes you can use "Die out" instead a verb "Thin out", if it concerns topics such as decrease to a point.