| noun | an act that violates the rules of a sport |
| verb | hit a foul ball |
| verb | make impure “The industrial wastes polluted the lake” |
| verb | become or cause to become obstructed “The leaves clog our drains in the Fall” |
| verb | commit a foul; break the rules |
| verb | spot, stain, or pollute “The townspeople defiled the river by emptying raw sewage into it” |
| verb | make unclean “foul the water” |
| verb | become soiled and dirty |
| adjective | highly offensive; arousing aversion or disgust “a disgusting smell” |
| adjective | offensively malodorous “a foul odor” |
| adjective | violating accepted standards or rules “a dirty fighter” |
| adjective | (of a baseball) not hit between the foul lines |
| adjective | (of a manuscript) defaced with changes “foul (or dirty) copy” |
| adjective | characterized by obscenity “had a filthy mouth” |
| adjective | disgustingly dirty; filled or smeared with offensive matter “as filthy as a pigsty” |
| adjective | especially of a ship's lines etc “with its sails afoul” |
| foul | verb | commit a foul; break the rules |
| foul | noun | an act that violates the rules of a sport |
| pollution | noun | the state of being polluted |
| polluter | noun | a person or organization that causes pollution of the environment |
| pollutant | noun | waste matter that contaminates the water or air or soil |
| contaminative | adjective | making impure by contact or mixing |
| contamination | noun | a substance that contaminates |
| contaminant | noun | a substance that contaminates |
| clog | noun | any object that acts as a hindrance or obstruction |
| backup | noun | an accumulation caused by clogging or a stoppage |
| congestive | adjective | relating to or affected by an abnormal collection of blood or other fluid |
| congestion | noun | excessive crowding |
| befoulment | noun | the state of being polluted |
| defilement | noun | the state of being polluted |
| defiler | noun | a person or organization that causes pollution of the environment |
| macula | noun | a patch of skin that is discolored but not usually elevated; caused by various diseases |
| maculation | noun | the act of spotting or staining something |
| disgustingness | noun | extreme unpalatability to the mouth |
| distastefulness | noun | the quality of being offensive |
| loathsomeness | noun | the quality of being disgusting to the senses or emotions |
| repel | verb | fill with distaste |
| skank | noun | any substance considered disgustingly foul or unpleasant |
| wickedness | noun | the quality of being disgusting to the senses or emotions |
| fetidness | noun | the attribute of having a strong offensive smell |
| foulness | noun | the attribute of having a strong offensive smell |
| noisomeness | noun | the quality of being noxious |
| smell | noun | any property detected by the olfactory system |
| filth | noun | an offensive or indecent word or phrase |
| filthiness | noun | moral corruption or pollution |
| nastiness | noun | malevolence by virtue of being malicious or spiteful or nasty |
| smuttiness | noun | obscenity in speech or writing |
| smut | noun | an offensive or indecent word or phrase |