What is Basket?

Legal Definition
A basket is a container which is traditionally constructed from stiff fibers, which can be made from a range of materials, including wood splints, runners, and cane. While most baskets are made from plant materials, other materials such as horsehair, baleen, or metal wire can be used. Baskets are generally woven by hand. Some baskets are fitted with a lid, others are left open.
-- Wikipedia
Legal Definition
A small PORTFOLIO of ASSETS that can be bought or sold or used as a reference in a DERIVATIVE contract. Baskets can be created out of securities or contracts from similar or different sectors/countries, depending on the specific HEDGING or investing goals being sought. See also OPTION, SWAP.