Word designating something as being representative of a whole

Solution 1:

I believe you're looking for epitome:

a perfect example: an example that represents or expresses something very well

Solution 2:

embodiment is quite close to the equivalent of synecdoche without the specific denotation of a literary device: someone or something that is a perfect representative or example of a quality, idea, etc.; the representation or expression of something in a tangible or visible form.

Mother Theresa was the embodiment of devotion to others; she was selflessness itself.

Other words that mean the same thing: image, incarnation, incorporation, manifestation, personification, realization, substantiation; quintessence, archetype, exemplar.

Solution 3:

exemplar comes to mind:

a typical example or instance; an orignal or archetype

Solution 4:

Provided you're using it for some positive quality (or you are feeling cynical), you could use Paragon.

A person of preeminent qualities, who acts as a pattern or model of some given (especially positive) quality.

Solution 5:

Quintessence - the purest or most typical instance