pile

1. Origins, structure, and basic meaning

• Structure: 堆 is associated with piling up; its on-reading is たい.
• Basic usage: 堆積(たいせき) means sedimentation or accumulation, while 堆肥(たいひ) means compost made from materials such as fallen leaves or vegetable scraps.

2. Common pitfalls and similar expressions

• Deposited sand and accumulated dust
  • 川底の砂の堆積 refers to sand deposited on a riverbed. ほこりが堆積している means that dust has accumulated, showing the same word used for an everyday buildup.