Means exchangeable. Interchangeable items are objects which, in terms of size, quantity or weight, are quantifiable and, therefore, interchangeable. Interchangeable goods or securities can only be traded on the stock exchanges, i.e. they are not mutually exchangeable or interchangeable. Banknotes, for example: a 50 Deutschmark note is interchangeable with any other. Goods can be rendered interchangeable by standardisation.