The bust in silhouette emoji represents an anonymous person.
Unicode: U+1F464
The bust in silhouette emoji (👤) depicts the silhouette or outline of a human bust or head. It is often used to represent an unidentified or anonymous person. This emoji can be useful when referring to someone without naming them specifically.
"I received a message from 👤, but I don't know who it is."
"The instructions say to ask 👤 at the front desk for assistance."
"My social media profile has a 👤 as the default avatar."