save for rainy day

stock, fund, mine, vein, lode, quarry; spring; fount, fountain; well, wellspring; milch cow., stock in trade, supply; heap (collection); treasure; reserve, corps de reserve, reserved fund, nest egg, savings, bonne bouche., crop, harvest, mow, vintage., store, accumulation, hoard, rick, stack; lumber; relay (provision)., storehouse, storeroom, storecloset; depository, depot, cache, repository, reservatory, repertory; repertorium; promptuary, warehouse, entrepot, magazine; buttery, larder, spence; garner, granary; cannery, safe-deposit vault, stillroom; thesaurus; bank (treasury); armory; arsenal; dock; gallery, museum, conservatory; menagery, menagerie., reservoir, cistern, aljibar, tank, pond, mill pond; gasometer., budget, quiver, bandolier, portfolio; coffer (receptacle)., conservation; storing; storage.