foul

1 foul /ˈfawəl/ adjective
fouler; foulest
1 foul
/ˈfawəl/
adjective
fouler; foulest
Britannica Dictionary definition of FOUL
[or more foul; most foul]
1 
: very unpleasant to taste or smell
3 
: very bad or unpleasant
4 
: indecent and offensive
— see also foul-mouthed
5 
: very unfair : not morally or socially acceptable
— see also foul play
6 
baseball : outside the area between the foul lines
◊ A foul ball is a batted ball that lands in the area outside the foul lines.
— compare 1fair 8

fall foul of

: to get into trouble because of (the law, a rule, etc.)

— foully

adverb

— foulness

noun [noncount]
2 foul /ˈfawəl/ noun
plural fouls
2 foul
/ˈfawəl/
noun
plural fouls
Britannica Dictionary definition of FOUL
[count]
1 
sports : an action that is against the rules and for which a player is given a penalty
— see also personal foul, professional foul, technical foul, foul out at 3foul
2 
baseball : a batted ball that lands outside the foul lines : a foul ball — see also foul out at 3foul

cry foul

— see 1cry
3 foul /ˈfawəl/ verb
fouls; fouled; fouling
3 foul
/ˈfawəl/
verb
fouls; fouled; fouling
Britannica Dictionary definition of FOUL
1 
[+ object] : to make (a substance, place, etc.) dirty
2 
sports
a  [no object] : to commit a foul
b  [+ object] : to commit a foul against (another player)
3 
[+ object] baseball : to hit (a pitched ball) so that it lands outside the foul lines — often + off
4 
[+ object] : to become twisted around (something) so that it cannot move, be used, etc.

foul out

[phrasal verb]
1 
basketball : to be forced to leave a game because you have made too many fouls
2 
baseball, of a batter : to make an out by hitting a foul fly ball that is caught by a fielder

foul up

[phrasal verb] informal
1 
foul (something) up : to ruin or spoil (something) : to ruin or spoil (something) by making a mistake or being careless
2 
: to make mistakes : to fail at something because you have made a mistake or been careless
— see also foul-up