Slang: Head doctor

Definition: A psychiatrist; a doctor who helps people with mental problems.

Example:

1) I've been seeing a head doctor for several years. 

2) You seem emotionally disturbed. Maybe you ought to see a head doctor?

Etymology: Psychiatrists are medical doctors who treat the mind, which is related to the brain, which is in the head. 

Synonyms: shrink

fonte: www.peakenglish.com