stockpile
[noun]
Synonyms: pile, bank, drift, heap, hill, mass, mound, mountain, pyramid, stack, reserve, backlog, hoard, inventory, nest egg, reservoir, stock, store
[verb]
Synonyms: accumulate, amass, cumulate, garner, hive, lay up, roll up, store (up), uplay

[TahlilGaran] English Synonym Dictionary ▲

I. stock‧pile¹ /ˈstɒkpaɪl $ ˈstɑːk-/ noun [countable]
a large supply of things that is kept ready for use in the future Synonym : store
stockpile of
a stockpile of nuclear weapons

[TahlilGaran] Dictionary of Contemporary English ▲

II. stockpile² verb [transitive]
to keep adding to a supply of goods, weapons etc that you are keeping ready to use if you need them in the future:
An enormous volume of explosives was stockpiled inside one of the buildings.

[TahlilGaran] Dictionary of Contemporary English ▲