1. (

• foul ,

) hit a foul ball ;

2. (

• pollute ,
• foul ,
• contaminate

) make impure; "The industrial wastes polluted the lake" ;

3. (

• clog ,
• choke_off ,
• clog_up ,
• back_up ,
• congest ,
• choke ,
• foul

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

4. (

• foul

) commit a foul; break the rules ;

5. (

• foul ,
• befoul ,
• defile ,
• maculate

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

6. (

• foul ,

) make unclean; "foul the water" ;

7. (

• foul

) become soiled and dirty ;

1. (

• befouled ,
• fouled

) made dirty or foul; "a building befouled with soot"; "breathing air fouled and darkened with factory soot" ;

2. (

• afoul ,
• foul ,
• fouled

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