Definition: Medium-term notes
External debt - IMF
These are debt instruments of usually one- to five-year maturity issued in bearer form under a program agreement through one or more dealers. Once a program is set up, issues can be made quickly to take advantage of market conditions, with issues structured more closely to investors’ needs than in the public bond markets. Typically, the MTN market is not as liquid as the international bond market, so issuers may have to pay a higher interest rate.
International Monetary Fund (IMF), "External Debt Statistics: Guide for Compilers and Users; Appendix I. Specific Financial Instruments and Transactions: Classifications", Washington D.C., 2003