[noun] an act that violates of the rules of a sport
[verb] hit a foul ball
[verb] make impure; "The industrial wastes polluted the lake" Synonyms:pollute, contaminate
[verb] become or cause to become obstructed; "The leaves clog our drains in the Fall"; "The water pipe is backed up" Synonyms:clog, choke off, clog up, back up, congest, choke
[verb] commit a foul; break the rules
[verb] spot, stain, or pollute; "The townspeople defiled the river by emptying raw sewage into it" Synonyms:bedefile, maculate
[adjective] violating accepted standards or rules; "a dirty fighter"; "used foul means to gain power"; "a nasty unsporting serve"; "fined for unsportsmanlike behavior" Synonyms:cheating, dirty, unsporting, unsportsmanlike
[adjective] (of a baseball) not hit between the foul lines
[adjective] (of a manuscript) defaced with changes; "foul (or dirty) copy" Synonyms:dirty, marked-up
[adjective] thoroughly unpleasant; "filthy (or foul or nasty or vile) weather we're having" Synonyms:filthy, nasty, vile
[adjective] characterized by obscenity; "had a filthy mouth"; "foul language"; "smutty jokes" Synonyms:filthy, nasty, smutty
[adjective] disgustingly dirty; filled or smeared with offensive matter; "as filthy as a pigsty"; "a foul pond"; "a nasty pigsty of a room" Synonyms:filthy, nasty
[adjective] especially of a ship's lines etc; "with its sails afoul"; "a foul anchor" Synonyms:aed