listed security

Securities that have been accepted for trading purposes by a recognized and regulated exchange.

Investopedia Says:
Listed securities have the advantage of higher liquidity within a regulated environment. In addition, investors are able to find accurate information on all listed companies.

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Stock or bond that has been accepted for trading by one of the organized and registered securities exchanges in the United States, which list more than 6,000 issues of securities of some 3,500 corporations. Generally, the advantages of being listed are that the exchanges provide (1) an orderly marketplace; (2) liquidity; (3) fair price determination; (4) accurate and continuous reporting on sales and quotations; (5) information on listed companies; and (6) strict regulations for the protection of security holders. Each exchange has its own listing requirements, those of the New York Stock Exchange being most stringent. Listed securities include stocks, bonds, convertible bonds, preferred stocks, warrants, rights, and options, although not all forms of securities are accepted on all exchanges. Unlisted securities are traded in the Over-The-Counter market. See also Listing Requirements; Stock Exchange.

Stocks and bonds traded on an organized security exchange such as the New York Stock Exchange (NYSE) and the American Stock Exchange (AMEX). They are distinguished from unlisted securities, which are traded in the Over-The-Counter (OTC) Market. The organized exchanges have certain requirements that firms must meet before their stock can be listed. Among the requirements are size of the company, number of years in business, earnings record, number of shares outstanding, and market value of shares.

The noun has one meaning:

Meaning #1: a security that has been accepted for trading by one of the organized and registered securities exchanges in the US
  Antonym: unlisted security (meaning #1)