foul

an act that violates the rules of a sport

hit a foul ball

make impure; "The industrial wastes polluted the lake"

become or cause to become obstructed; "The leaves clog our drains in the Fall"; "The water pipe is backed up"

commit a foul; break the rules

spot, stain, or pollute; "The townspeople defiled the river by emptying raw sewage into it"

make unclean; "foul the water"

become soiled and dirty

highly offensive; arousing aversion or disgust; "a disgusting smell"; "distasteful language"; "a loathsome disease"; "the idea of eating meat is repellent to me"; "revolting food"; "a wicked stench"

offensively malodorous; "a foul odor"; "the kitchen smelled really funky"

violating accepted standards or rules; "a dirty fighter"; "used foul means to gain power"; "a nasty unsporting serve"; "fined for unsportsmanlike behavior"

(of a baseball) not hit between the foul lines

(of a manuscript) defaced with changes; "foul (or dirty) copy"

characterized by obscenity; "had a filthy mouth"; "foul language"; "smutty jokes"

disgustingly dirty; filled or smeared with offensive matter; "as filthy as a pigsty"; "a foul pond"; "a nasty pigsty of a room"

especially of a ship's lines etc; "with its sails afoul"; "a foul anchor"