鏡|かがみkagami[3]odaka (tail-high)

1. nounmirror; looking-glass
   海うみは鏡かがみのようになめらかだった。↗

   The sea was as smooth as glass.
2. nounbarrel head
3. noun, financepage added at the beginning of a document mentioning its purpose, date, author, etc.
4. nounmirror-shaped mochi

• SynonymミラーCasualA loanword for mirror, used mostly for car mirrors and in compounds such as 「バックミラー」; for an ordinary mirror, 「鏡」 remains the default word.
• Related鏡鑑きょうかんWrittenWritten/formal prose term for a metal mirror; figuratively it also means a model to learn from. Rare, and never replaces 「鏡」 in everyday use.
• Related鑑かがみNeutralWhen written 「鑑」, it means a model or paragon, as in 「教師の鑑」; unlike 「鏡」, it is not used for a mirror that reflects your image.

Use 「鏡」 for any mirror by default. Choose 「ミラー」 for car mirrors and compounds, 「鑑」 for a model or paragon like 「教師の鑑」, and 「鏡鑑」 in formal prose for a metal mirror or one to learn by.

Usage comparisons are AI-assisted and cross-checked by multiple models; for study reference only

1. （かがみ）光ひかりの反射はんしゃを利用りようし、姿すがたを映し出うつしだす道具どうぐ。最もっとも古ふるくは、水盆すいぼんに水みずを張はり姿すがたを映うつしていたが、やがて金属きんぞくを磨みがくことにより作つくるようになり、現在げんざいでは平面へいめんにしたガラスに銀ぎんなどをめっきして作つくる。