accumulation
accumulate + -ation
https://gyazo.com/ee885ad1034bf06ecc6ea6a76b516879
source: bandai GIF - Find & Share on GIPHY
noun
the acquisition or gradual gathering of something: 何かの収集物、徐々に集めること
uncountable.icon 蓄積, 積み重ね; 利殖; countable.icon 蓄積物, たまった物
e.g. the accumulation of wealth.: 富の蓄積
a mass or quantity of something that has gradually gathered or been acquired: 徐々に集められた、入手されたものの集まり、量
e.g. the accumulation of paperwork on her desk.: 彼女の机の上の書類の山