Having the ascendency over others; superior in strength, influence, or authority; prevailing; as, a predominant color; predominant excellence
If something is predominant, it is more important or noticeable than anything else in a set of people or things. Amanda's predominant emotion was that of confusion. more powerful, more common, or more easily noticed than others
You use predominantly to indicate which feature or quality is most noticeable in a situation. a predominantly female profession = mainly, largely. mostly or mainly