look up any word, like the eiffel tower:
 
1.
1) A guy and a girl who are constantly having sex.

2) A guy and a girl who are never apart.

Really, a peg that does not withdraw from its socket, such as a tooth — but you can see why its meaning changed.
Nate and Lisa are, like, gomphosis.
by knightshade December 10, 2004