Answer:
a security that can be converted into any other type of security.
Step-by-step explanation:
Convertible securities are securities (e.g. bonds) that can be converted into another security, usually into common or preferred stock, after an specified term of conversion ends. This specific term of conversion is set when the original security was issued.
The most common types of convertible securities are convertible bonds (that can be converted into common or preferred stock) and convertible preferred stock (that can be converted into common stock).