The loanword 'Miss' used as a title/prefix; placed before a name to indicate an unmarried or young woman.
ミス田中が今日の司会を務めます。
Miss Tanaka will be the host today.
ミス・コンテスト（ミスコン）で優勝したのは彼女だ。
She is the one who won the beauty contest (Miss contest).
英語では既婚ならＭｒｓ.、未婚ならＭｉｓｓを使う。
In English, you use Mrs. for married women and Miss for unmarried women.
An unmarried woman (noun). Often used in titles or older expressions (e.g. 'Miss Japan').
彼女は若いころミス日本に選ばれた。
She was chosen as Miss Japan when she was young.
昔は『ミス』という呼び方が一般的だったが、最近はあまり使われないこともある。
In the past the term 'Miss' was common, but nowadays it is sometimes not used much.