look up any word, like trill:
 
1.
Dictionary Definition: Refers to a girl, who wants a guy so badly, that the girl can be successfully sexually solicited by the previously said guy.

Alternate Definition:
On the tip (of his penis)
Dude, He has totally has her on the tip.
by The_Teacher August 01, 2008
 
2.
Adj, prepositional phrase to be used with the intransitive verb "is,"
On top of the situation, doing well. Excellent.
Man, that was great. You're on the tip.
by jbmonday October 13, 2003