The insertion of the head into the anus of another.

A stupid person; it refers to the lack of surface area on an individual's brain. The general thought is that the more surface area (wrinkles, creases, etc.) a brain has, the smarter the person is. Conversely, a person with a smooth brain (no wrinkles) has less surface area and would therefore be stupid.

The act of putting your head (the one on your shoulders) into a vagina or butt.

So me and my buddy were walking to school seventh grade year and we were talking about sex. Well I just saw a video of a guy putting his whole head in this girl's vagina and I was like "let's call it heading".

when lesbien 1 spreds her legs and when lesbien 2 bends over with a lubed up head and runs towards lesbien 1 and inseerts her head into liesben 1 minge repeatly for added pleasure

The ACTUAL definition of heading is heeding reading a book.

When someone puts their head inside of a vagina