accumulate
verb
uk/əˈkjuːmjəleɪt/ us [ I ]
to gradually increase in amount:
While the deficit was allowed to accumulate, nothing was done to address the problem.
[ T ]
to collect an amount of something over a period of time:
The table shows what you need to save monthly to accumulate $1 million by age 65.
accumulate/debts/losses/wealth The report also said a further 90,000 households had accumulated wealth of more than £1m.