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.

---

Etymology

Origin of index fund

First recorded in 1975–80

Example Sentences

See Examples For:

index fund

His will calls for his widow to invest 90% of her inheritance in an S&P 500 index fund and 10% in short-term Treasurys.

From The Wall Street Journal ● Sep. 24, 2026

But for investors, an equal-weighted index fund logically makes more sense.

From MarketWatch ● Aug. 31, 2026

If SpaceX is allowed to try really hard to infiltrate your sensible money-market index fund, why not put it into something you’re actually passionate about, like an ultra-rare mint condition Umbreon card?

From Slate ● Aug. 31, 2026

Meanwhile, if you are buying a traditional S&P 500 index fund, right now, 8% of your money is going into one stock: Nvidia.

From MarketWatch ● Aug. 31, 2026

It would be foolish to start a new, even cheaper S&P 500 index fund today to steal market share.

From The Wall Street Journal ● Aug. 21, 2026