Obligatory Adderall Shit. This phenomenon occurs approximately between 30 minutes and 2 hours after the consumption of Adderall. OAS' usually comes out of nowhere and require immediate location of a restroom.

something you say when you're too lazy to say "Ok".

abbreviation of Old Ass SHIT! O-ld A-ss S-hit
When someone has a bunch of junk lying around collecting dust and broken they have OAS.

Oa is a dumb ass that has small pp

Oa, a hot boy who can do anything and get all the girls

g oa oas

In switzerland there's a famous rap-group called oa.
Somehow they managed it to make people say oa instead of awesome, fresh, good, cool etc.

so when you get to switzerland make sure, to know the meanings of "oa". (adjektive)