Top definition
1. Adjective. When an individual exhibits or develops behaviors in the autism spectrum, at an advanced age. Typically occurring from misdiagnoses or underreported cases. Affects ages 19-50, NEETs, and many a weeaboo.

Symptoms: increase in frequency of dropping Spaghetti and general lack of self awareness at an age where one is supposed to be accustomed to social norms and rules of social engagement.
"Yeah, that guy has Adult Onset Autism or something. He won't shut up about video games at the bar when all these cute girls walk by."
by DuedBraj December 25, 2014
Get the mug
Get a Adult Onset Autism mug for your cousin José.