1 pile, heap, mound, mass, accumulation, hill, mountain, store, stock, bank, deposit, supply, stockpile, hoard, load, bundle, bale, Colloq US and Canadian stash:
This stack of paper ought to be enough to last through the next printing.
2 haystack, cock, haycock, rick, rickle, hayrick, Brit clamp:
The stacks were covered with a tarpaulin before it started to rain.
3 collection, aggregation, accumulation, agglomeration, amassment, mass, load, pack, amount, abundance, plenty, profusion, volume, array, sea, throng, multitude, swarm, host, number, quantity, pile-up:
We have a huge stack of orders to process this morning.
4 smokestack, chimney, chimney-stack, funnel; Building soil stack:
They built the stack very tall to carry the fumes away from the town below.
5 blow one's stack. anger, become angry, become furious or infuriated, rage, rant, lose one's temper, Slang blow or lose one's cool, get hot under the collar, blow one's top:
The boss will blow his stack if we miss the deadline.
6 Often, stack up. pile (up), heap, accumulate, amass, store, stock, stockpile, hoard, collect, aggregate, agglomerate, Colloq stash (away), squirrel away:
Stack those boxes neatly in the corner. Has he stacked up enough points to qualify?
7 stack up.
(a) make sense, add up, agree, jibe, be verifiable, Colloq check out:
The ledgers don't stack up with the cheque-book. The two sets of figures simply don't stack up.
(b) compare, measure up, hold a candle to, be on a par (with), be as good as:
He could never stack up to Olivier.