A cover or protective layer—such as a book cover, dust jacket, slipcover, or phone cover.
新しい本に透明のカバーをかけた。
I put a clear cover on the new book.
ソファのカバーは洗える素材を選ぶと便利だ。
It's convenient to choose a sofa cover made of washable material.
スマホのカバーを買い替えた。
I replaced my smartphone cover.
A cover version of a song—the act of performing or recording an existing song by a different artist, or that rendition.
彼女は有名な曲をカバーしてアルバムを出した。
She covered a famous song and released an album.
ライブでバンドがビートルズの曲をカバーした。
The band covered a Beatles song at the live show.
このカバーは原曲と雰囲気が違って面白い。
This cover has a different vibe from the original and is interesting.
Coverage—used for media coverage (reporting) or insurance/financial coverage (the scope that is covered).
今回の事件は全国ニュースで大きくカバーされた。
This incident was widely covered by the national news.
この保険は海外での医療費もカバーしている。
This insurance also covers medical expenses abroad.
To cover (a loss), offset or compensate for a weakness; also to cover for someone by doing their work—expressed as the verb 'カバーする'.
彼はチームの欠点をスキルでカバーした。
He covered the team's weaknesses with his skills.
売上減を他の商品でカバーできるか検討している。
We're considering whether we can offset the drop in sales with other products.
急用で休む同僚の仕事を明日カバーするよ。
I'll cover for my coworker who has to take an emergency day off tomorrow.