Mental Block
When you completely ignore someone.
Example 1:
Person 1: Dave?
Person 1: Davveee?!

Person 1: OOh you putting a mental block on me ehh?

This can then be adapted for wherever you are such as a room block.
Example 2:
Person 1: Dave?

Person 2: Alright Dave how are ya?

Person 3: Hes put a room block on us all.