• Webster's Revised Unabridged Dictionary
    • Defoul To make foul; to defile. "All his hairy breast with blood was filed .""For Banquo's issue have I filed my mind."
    • Defoul To tread down.
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Century Dictionary and Cyclopedia
    • defoul To make foul or unclean; befoul; defile.
    • n defoul Defilement; soiling.
    • defoul To trample upon; press down; crush, as by trampling.
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Chambers's Twentieth Century Dictionary
    • v.t Defoul de-fowl′ to defile.
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Webster's Revised Unabridged Dictionary
See Defile (v. t.)
Chambers's Twentieth Century Dictionary
A.S. fúl, foul, whence by vowel change of ú to ý, fýlan.


In literature:

Defoule (je), 680, 761.
"An Introductorie for to Lerne to Read, To Pronounce, and to Speke French Trewly" by Anonymous

In news:

A Connecticut technology start-up has patented a multilayer composite polymer coating system that can de-ice aircraft in flight and defoul periscope head windows in service.