"Stash" came into modern usage through the drug culture; referencing someone's dope cache.
Before, 'to stash' simply meant to put something away for future need and 'stash' was the noun. It implies secrecy.......Squirrels stash nuts, nuts stash guns and ammo, the thrifty stash cash under the mattress and the revenue officers look for the moonshine stash.
"Stash" is also short for the hairy growth above the mouth.
If I'm not religiously careful to depilate, my quilter's stash will be seen on my upper lip.