accumulateac·cu·mu·late /əˈkjuːmjəleɪt/ verb1[transitiveT] to get, earn, or obtain something gradually over a period of timeHe had accumulated $20,000 in interest.
A lot of companies have accumulated significant debts.
2[intransitiveI] to increase or develop gradually over a period of timethe funds that had accumulated in their accounts
The arrears have been accumulating since last year.
—accumulated adjectiveadj [only before a noun]The firm now has $300,000 of accumulated debt.