Polymail makes it easy to block emails from senders you don't want. Any senders that you block will have their messages automatically moved to your Trash folder.
Blocking Senders on Web and Desktop
Just click on the sender's name or click on the three horizontal dots on the message:
Managing Blocked Senders
You can choose where you want to send messages from senders you have blocked, and manage senders that you have blocked in Settings > Blocked Senders
Blocking Senders on IOS
Block a sender on iOS simply by tapping on the 🚫 icon at the bottom right bar when viewing a message!