Antonyms for more polluted

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Roget's 21st Century Thesaurus, Third Edition Copyright © 2013 by the Philip Lief Group.

EXAMPLES FROM THE WEB FOR MORE POLLUTED

The waters grew more and more polluted; but new myriads came up momentarily and plunged in, heedless of everything but thirst.

As we entered the streets, Tommies more polluted than miners crept out from the skeletons of houses.

The more polluted the inside of the sepulchre is, the more shining and white the outside will be kept.