accumulating
v.v. to collect or gather more and more of something over a period of time.
v. to gather or acquire an increasing quantity of something over time. Often describes the gradual buildup of physical objects, wealth, or abstract data.
Dust is accumulating on the old books in the attic.
The company is accumulating a large amount of debt by expanding too quickly into new markets.
By accumulating small advantages in every department, the team eventually secured a victory that seemed impossible at the start of the season.
The verb is both transitive and intransitive; it can describe something you do to an object or something that happens on its own.
He is accumulating of wealthHe is accumulating wealthAccumulate is a transitive verb and does not require the preposition 'of' before its object.