Vanilla option Definition
In finance, a vanilla option is a type of derivative security. Though the term is very widely used throughout the financial literature and the financial markets it lacks a precise definition. Generally speaking a vanilla option is a 'simple' option in some sense. e.g. a particular type of option may be described as vanilla if it is well-established in the financial markets and is easy to trade - vanilla options typically have good liquidity at a wide range of strike prices and maturities.