granny arms 

The flap of loose skin that hangs under old women's upper arms when they are extended.

When its hot out, my Nana's granny arms work better than a fan when she flaps them.

granny arms by the Den of Iniquity December 27, 2006

Grannyarse 

A bottom, rear-end, arse, ass which has drooped over time.

The tattoo on her grannyarse was so stretched out of shape that is could only be read by someone with lemon shaped corneas

Grannyarse by kerfoofle November 5, 2010