foul play

Noun

1.

foul play - unfair or treacherous behavior (especially involving violence)

artifice, assassination, blood, bloody murder, bumping-off, chicane, chicanery, collusion, connivance, connivery, conspiracy, covin, crime, deception, dirty pool, dirty trick, dirty work, dodgery, double-dealing, duplicity, elimination, falseheartedness, foul, guile, hanky-panky, homicide, killing, liquidation, machination, manslaughter, murder, perfidiousness, perfidy, pettifoggery, pettifogging, purge, purging, removal, sharp practice, skulduggery, sleight, supercherie, thuggee, thuggery, thuggism, treacherousness, treachery, trickery, underhand dealing, unfairness, unsportsmanlikeness, unsportsmanliness