A group providing caracteristic properties to a molecule is called functional group or function.
If a molecule has several such functions, one of those has the precedence for the suffix (exception: alkyl halides), all the others are stowed in prefix in alphabetical order. The following table lists the functional groups by order of precedence :
Comments: - In case of an asterisk *, the carbon atom of the functional group is not part of the main chain ( see details here ). For example, OHCCO(NH2) is called formylmethanamide (blue: the main chain) and not formylethanamide - There are 3 (!) systems of nomenclature for the amines ( see details here ).