Index fund

An index fund or index tracker is a collective investment scheme (usually a mutual fund) that aims to replicate the movements of an index of a specific financial market, or a set of rules of ownership that are held constant, regardless of market conditions.Tracking can be achieved by trying to hold all of the securities in the index, in the same proportions as the index. Other methods include statistically sampling the market and holding "representative" securities. Many index funds rely on a computer model with little or no human input in the decision as to which securities to purchase and is therefore a form of passive management.
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Noun
1. a mutual fund that invests in the stocks that are the basis of a well-known stock or bond index
(hypernym) mutual fund, open-end fund, open-end investment company

Investment fund designed to match the returns on a stock market index. Mutual fund whose portfolio matches that of a broad-based index such as the S&P 500 and whose performance therefore mirrors the market as represented by that index.