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

See Examples For:

index fund

The top five holdings in an S&P 500 index fund account for 29% of the fund by value, if you can believe it.

From MarketWatch ● Jul. 14, 2026

Warren Buffett, living proof there’s such a thing as investing skill, famously bet a hedge fund executive that an S&P 500 index fund would beat five elite “funds of funds” over 10 years.

From The Wall Street Journal ● Jul. 14, 2026

By law, the money must be invested in a low-cost index fund designed for long-term growth.

From BBC ● Jul. 11, 2026

You might focus on the profit you made on that trade, without checking how much more you could have earned by holding an index fund.

From The Wall Street Journal ● Jul. 10, 2026

For every study showing faith funds keeping pace, there is another showing that some have delivered lower returns and higher volatility than a simple total-market index fund, with the extra risk going uncompensated.

From MarketWatch ● Jul. 6, 2026