1. Blocking or banning a user or group from a service or online platform due to their use of hate speech (or violating the platform's terms of service, etc.)
   "The social media company engaged in no-platforming of accounts that repeatedly spread misinformation";
   - deplatforming
    
2. Political activism with the goal of excluding or shutting down offensive or controversial speakers or speech
   "Students engaged in no-platforming efforts to prevent a controversial figure from speaking on campus";
   - deplatforming

Encyclopedia: No-platforming