Aging: the process of growing older and the resulting deterioration or changes in biological functions; can also refer to the degradation of materials or machines.
加齢による老化で記憶力が少しずつ落ちる人もいる。
Some people experience gradual memory decline due to aging.
機械部品の老化を防ぐために定期点検が必要だ。
Regular inspections are necessary to prevent aging of mechanical parts.
肌の老化対策として日焼け止めの使用が勧められる。
Using sunscreen is recommended as a measure against skin aging.