When a male gets his anus tongued from behind while simultaneously having his meat yanked. The first oxidized brass instrument originated in Florence, Italy between Ms. Lisa and Mr. da Vinci. Historians believe the frown on Mona Lisa is a result of the oxidation from the direct contact of Leonardo da Vinci’s butthole with her lips. Also see Rusty Trombone
A quality in a girl who is found to be attractive though not based primarily upon looks. 'Omijion' is judged on first glances via an apparent presence of personality and sense of humour which are all vital contributing elements.
"that girl has omijion"
"Omijion??"
"I'm calling omijion...."