Noun. Often facetious or derogatory. The blending, or portmanteau, of Brain Fart and AARP. A lapse in memory or thought for those not quite old enough to be having a Senior Moment but being close to or having reached the minimum membership age (50) of AARP.
"He forgot his cell phone again? If he has one more brain fAARP, we'll just start calling him grandpa."
by rqd January 11, 2012