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Webster 1913 Edition
Afoul
A-foul′
,adv.
& Adj.
[Pref.
a-
+ foul
.] In collision; entangled.
Totten.
To run afoul of
, to run against or come into collision with, especially so as to become entangled or to cause injury.
Webster 1828 Edition
Afoul
AFOUL'
,adv.