self-purification

noun

self-pu·​ri·​fi·​ca·​tion ˌself-ˌpyu̇r-ə-fə-ˈkā-shən 

-ˌpyər-

1

: purification by natural process

self-purification of water

2

: purification of oneself

Word History

First Known Use

1654, in the meaning defined at sense 2