1A cream or lotion applied to the skin to prevent sunburn/tanning from UV rays; often labeled with an SPF rating.
海に行く前に日焼け止めをしっかり塗ってください。
Make sure to apply sunscreen thoroughly before going to the beach.
敏感肌用の日焼け止めを買ってみた。
I bought sunscreen for sensitive skin.
日焼け止めはこまめに塗り直す必要がある。
You need to reapply sunscreen frequently.