constituent stock; component issue
Used in finance for the individual stocks or securities that make up an index or portfolio.
The constituent stocks of the Nikkei Stock Average are reviewed periodically.
This fund's constituent issues include many major companies.
銘柄 is a general term for a stock or brand, while 構成銘柄 specifically refers to a stock that is part of an index or portfolio.
Compound of 構成 (composition) and 銘柄 (stock issue).