badmouth russian

• обга́дить

  to soil, to befoul, to make dirty, to mess up

  to badmouth, to denigrate, to slander, to spoil, to trash

• нагова́ривавший

  slandering, defaming, calumniating, badmouthing

  recording, dictating (audio)

• перемыва́вший

  who was washing all, who had been washing all, who was rewashing

  who was gossiping, who was badmouthing

• перемыва́ющий

  rewashing, washing (all/many things), washing again

  gossiping, slandering, badmouthing