a Bishop (or Archbishop) in the Catholic Church, referring to the characteristic headgear they wear (aka the miter), and possibly also to definition #1 as an important characteristic for conehead. Honestly, the first time I heard this definition of conehead was from a Catholic Priest.
Coneheading is a sexual act that involves a male (or female) strapping a strap-on dildo around their head and using it to penetrate their male (or female) partner.
"man, I was so drunk I couldn't get it up last night, but she had a strap on so we were coneheading for hours!"
By Cassy
ConeHead
An individual who induldges dayly in a conepiece,filled with marajuana,connected to a smoking device usually a bong