big oxygen levels

1. A compliment, meaning you have large amounts of oxygen, therefore having more brainpower.
2. An insult, meaning you have lots of oxygen in your head, and very little brain.
The big can also be replaced with other words describing size, such as massive or huge.
Good luck figuring out which.

Def 1: Dude, he just aced the test. Must have big oxygen levels.
Def 2: Wow, you play Fortnite? You have MASSIVE oxygen levels.