What Does The Suffix 'Action' Mean?

When you are using the word 'action' as a suffix, you are conveying the idea of exerting a force that brings about the effect by which the result can be produced from the inherent capacity of the agent.
       
To understand the word well you should understand the word in its context. If we take the example of the word 'fraction', it is formed by the amalgamation of two words 'fragment' and 'action' and the use of the word conveys the idea of effect of something in smaller parts. As we all know that fragment conveys the idea of something very small, the meaning of the word is justifying itself.
       
Sometimes the word is also being used independently and the meaning you can figure out from the use of the word is same as that of the when it is used in association with the word.