Top definition
A descriptive word for someone ass.
Ussually a good thing - meaning one has a 'mountable' ass
Jane says 'Damn, look at the ass on him. VERY mountainous'

Sara says 'Yeah, for sure, bet that's what his boyfriend thinks too.'
by Sofaqueen March 10, 2008
Get the mug
Get a Mountainous mug for your Aunt Yasemin.