accumulate

Universal Words verb 1 [VN] to gradually get more and more of sth over a period of time: I seem to have accumulated a lot of books. * By investing wisely she accumulated a fortune. * We have accumulated a great amount of evidence. 2 [V] to gradually increase in number or quality over a period of time SYNBUILDUP: Debts began to accumulate. * Dust and dirt soon accumulate if a house is not cleaned regularly. accumulation noun [U,C]: the accumulation of wealth * an accumulation of toxic chemicals