When a player of a videogame has earned enough experience points to acquire a new level in a skill or skills. Often is accompanied by the ability to weild new weaponry, access new places, or begin new assignments.
When you've made the next round of existence on this earth.
Also known as a birthday, anniversary, of other significant date that marks an individual's evolution.
To level up, or leveling up, means to ingest magic mushrooms and trip. It is a clever play off of the classic Super Mario games, where obtaining mushrooms gave the player additional lives.
Euphemism used by nerds to infer that they've just gotten laid. As a result, this meaning tends not be be used that often in a non-ironic context.
Level Up:
My date with ____ went extremely well last night. The alcohol must have given be a bonus to charisma, because we headed back to her place and I totally levelled up.