Understanding the Distinction Between Indexes and Indices: Usage, History, and Examples

Difference Between Indexes and Indices

Words can sometimes be a little tricky. Let’s learn about the words “indexes” and “indices.” What do they mean? How do we use them? Let’s find out!

History

The word “index” comes from Latin. Long ago, people used “indices” for more than one index in math and science. But in everyday English, we also use “indexes.”

How to Use Them

Indexes

“Indexes” is the plural form of index. We mostly use it for books, lists, and databases. Here are some sentences:

• The book has three indexes at the end.
• She checked the indexes to find the right chapter quickly.
• Our library’s indexes help us find books easily.
• The teacher made indexes for the students’ projects.
• Please look at the indexes for more details.

Indices

“Indices” is mostly used in math, science, and when talking about markets or reports. Here are some sentences:

• The scientist studied the indices of light.
• In math class, we learned about different indices.
• The stock market indices went up today.
• The report showed various economic indices.
• For the exam, we need to understand these indices.

Trick to Remember the Difference

Think about the context. Use “indexes” for books and lists. Use “indices” for math, science, and finance.

Summary

Both “indexes” and “indices” are correct. “Indexes” is for regular lists or books. “Indices” is for science, math, and finance topics. Choose based on what you are talking about! Now you know the difference!