Not to be confused with "adult alternative", though it often is and kind of overlaps with it sometimes. Used to describe radio stations that play everything in rock that's typically not too "aggressive" or not too "soft", from The Beatles and Bob Dylan to The Shins and Modest Mouse and everywhere in between. Should NOT include John Mayer, Jason Mraz, James Blunt, etc. though unfortunately it often does. Sadly, most of the stations that play it tend to be closer to adult alternative than adult ALBUM alternative.
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."