Translation guide
The English word "index" has several distinct meanings. This guide covers the most common ones for learners: a list in a book, a sign or indicator, and a numerical measure. It also briefly covers the finger and the mathematical exponent.
The learner wants to refer to the list of topics with page numbers at the back of a book.
The standard word for an index in a book. Used in both spoken and written contexts.
この本の索引で調べてください。
Please look it up in the index of this book.
A loanword from English, often used in technical or IT contexts, but can also refer to a book index. Less common than 索引 in everyday book contexts.
インデックスを使って目的のページを探す。
Use the index to find the target page.
The learner wants to express that something is a sign or measure of a condition or trend.
A broad term for an indicator, index, or benchmark. Used in economics, social sciences, and general contexts.
GDPは経済の重要な指標です。
GDP is an important indicator of the economy.
Often used for numerical indices, like stock market indices or price indices. More mathematical than 指標.
A rough standard or yardstick; a guide. Used when something serves as a reference point rather than a precise measure.
The learner wants to refer to a specific numerical index, such as a price index or stock index.
The standard term for a numerical index. Used in economics, finance, and statistics.
消費者物価指数が発表された。
The consumer price index was announced.
The learner wants to refer to the finger next to the thumb.
The standard word for index finger. Literally 'person-pointing finger'.
人差し指で指してください。
Please point with your index finger.
A literary or formal term for the index finger. Rarely used in daily conversation; mostly appears in set phrases like 食指が動く (to be tempted).
The learner wants to refer to the small raised number indicating power in math.
The mathematical term for exponent. Also used in expressions like 指数関数 (exponential function).
2の3乗の指数は3です。
The exponent of 2 to the power of 3 is 3.
指標 is a broad indicator or benchmark, often qualitative. 指数 is a numerical index, like a stock index. 目安 is a rough guide or standard, not necessarily precise.
The loanword インデックス is not used for the index finger. Use 人差し指 instead.
The Nikkei Stock Average is a representative stock index of Japan.
This figure is only a rough guide.
Commonly used in finance and IT, often as part of compound terms like 株価インデックス (stock index).
このファンドはS&P500インデックスに連動しています。
This fund tracks the S&P 500 index.
to feel an urge to try something