Prevention or protective measures taken to guard against illness, accidents, or other harms (e.g., vaccination, precautions).
インフルエンザ予防のためにワクチンを打った。
I got a vaccine to prevent influenza.
事故予防のために安全講習を受ける。
Take safety training to prevent accidents.
手洗いやうがいは感染予防に有効だ。
Handwashing and gargling are effective for preventing infection.