寿命

1. Origins, structure, and basic meaning

• Structure: 寿命 is read as じゅみょう and is a noun for the lifespan of a living being or the service life of a device or component.
• Basic usage: A battery reaching the end of its life appears in 電池が寿命を迎える, while comparing animals appears in 動物ごとの寿命を比べる.

2. Common pitfalls and similar expressions

• Living beings and products
  • It applies both to how long a person or animal lives and to how long a battery or machine continues functioning properly.
• Difference from 命
  • 命 denotes life itself, whereas 寿命 focuses on the duration of that life or of a product's useful function.