index fund

American  

noun

1. a fund, as a mutual fund or pension fund, with a portfolio that contains many of the securities listed in a major stock index in order to match the performance of the stock market generally.

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Etymology

Origin of index fund

First recorded in 1975–80

Example Sentences

In an S&P 500 index fund, 47% of your money sits in only two industries, technology and communications, with nearly 8% in Nvidia alone.

From The Wall Street Journal • Jun. 12, 2026

Buying just that group would have left an investor with 80% less money than an S&P 500 index fund, taking inflation into account.

From The Wall Street Journal • Jun. 11, 2026

Accordingly, there has been a big push on the Street to stuff them into the leading stock indices, leaving index fund managers no choice but to buy.

From Los Angeles Times • Jun. 9, 2026

The iShares index fund, which began trading in 2000, also charges 0.03%.

From Barron's • Jun. 3, 2026

Will your index fund or ETF own these newly minted megacap stocks immediately, years from now or not at all?

From MarketWatch • Jun. 2, 2026