抹黑

mǒ hēimohei

1. to discredit
2. to defame
3. to smear sb's name
4. to bring shame upon (oneself or one's family etc)
5. to blacken (e.g. commando's face for camouflage)
6. to black out or obliterate (e.g. censored words)

Study it in Yanamino