Index Amortizing Note - IAN

A type of structured note whose payment schedule is determined by the behavior of interest rates.

Investopedia Says:
Similar to the maturity of a collateralized mortgage obligations, the maturity of an index amortizing note extends when interest rates rise and shortens when interest rates decline. Some investors, however, choose IANs as an alternative to CMOs since IANs are exposed to less extension and contraction risk.