1. To collect or to obtain a large amount of something over a period of time.
2. To gather or to pile up; to amass.
3. Etymology: When, in colloquial speech, a man refers to the accumulating of a fortune as "making his pile", he is using exactly the same figurative language as that which first suggested the word accumulate.

Cumulus is Latin for "a heap" or "pile", and cumulare means "to pile up:. With the prefix ad, "to", we have accumulare, "to heap together", which is the source of our English word accumulate.