1To pile things up one on top of another; to accumulate or build up (e.g., experience, knowledge) gradually.
箱を倉庫の片隅にきれいに積み重ねた。
We neatly stacked the boxes in a corner of the warehouse.
彼は若い頃から経験を積み重ねて今の地位を得た。
He accumulated experience from a young age and attained his current position.
ミスを積み重ねると信用を失うことがある。
Repeated mistakes can lead to loss of trust.