accumulation
US /əˌkjuː.mjəˈleɪ.ʃən/
UK /əˌkjuː.mjəˈleɪ.ʃən/

1.
积累, 堆积
the acquisition or gradual gathering of something
:
•
The accumulation of dust on the shelves was noticeable.
架子上灰尘的堆积很明显。
•
His wealth was the result of years of careful accumulation.
他的财富是多年精心积累的结果。