Unmatched Book
Where the maturities of assets and liabilities in a trader's or a firm's accounts, or book, do not correspond. More specifically, the term can refer to a situation where the average maturity of the liabilities is shorter than that of the assets. For a bank it can mean it has made long-term loans but has only short-term deposits which may be withdrawn before the loan assets are realised. Sometimes known as lending [Long|long]] and borrowing short.