I've often called a person a dickhead. I decided to see if there is a definition of dickhead and I found this.
dickhead /dÄk′hÄ•d″/
noun
An inept, foolish, or contemptible person.
The glans penis.
A jerk; a mean or rude person.
Describes trump to a "T".
The fun things we learn.
6 days ago