A jazz sus chord or dominant 9sus4 chord is a seventh chord on the fifth scale degree of the key with a suspended fourth and an added ninth. Functionally, it can be written as V9sus4 or V7sus9.
ISO (International Organization for Standardization) is an independent, non-governmental membership organization and the world's largest developer of voluntary International Standards.
According to ISO, ISO is not an abbreviation. It is a word, derived from the Greek isos, meaning equal, which is the root for the prefix iso- that occurs in a host of terms, such as isometric (of equal measure or dimensions) and isonomy (equality of laws, or of people before the law).