As a noun cache means a hiding place, and as a verb it means "to conceal": "The Joneses placed their silverware in a cache upstairs." "You had better cache that money somewhere so that it won't be discovered." Hide, the most commonly used of these three related words, means "to put or keep out of sight": "Hide that letter in the file." Stash is an informal word of unknown origin that means precisely what cache does. Differences in use are slight: cache involves concealment in a place unknown to others and suggests storage with a view to later use; hide refers to putting physical items out of sight and also to disguising or withholding one's thoughts and feelings. Substitutes for these three words include secrete, bury, conceal, screen, and cloak.
Dictionary of problem words and expressions. Harry Shaw. 1975.