stash (v.) Look up stash at Dictionary.com
"to conceal, hide," 1797, criminals' slang, of unknown origin, perhaps a blend of stow and cache. Related: Stashed; stashing.
stash (n.) Look up stash at Dictionary.com
"hoard, cache," 1914, from stash (v.). Slang sense of "personal supply of narcotics" is from 1942.