Zhenren, a term apparently coined by Zhuangzi himself, signifies the fully realized human being. It is variously translated as "True Man", "Genuine Man", or "Real Man". Roger Ames prefers "Authentic Person" (Wandering at Ease in the Zhuangzi; Introduction). Among his reasons, is his belief that it more faithfully conveys the root meaning of zhen which implies authorship and transformation. In other words, the Authentic Person is someone in the continual process of creative self-disclosure (ziran) in relation to the ever-transforming world. "That is", he writes, "whatever the exemplar might be, he or she is one who is able to express personal integrity and uniqueness in the context of a transforming world."
If there were more than one Authentic Person in the world, they would be very different expressions of the same authenticity. This is because such a person would not have realized some pre-existent, fixed and ideal 'original nature' common to all, but the unique expression of her own particularity. And not only this, her expression would also be a consequence of her transforming along with her particular and unique environmental context. Human authenticity is not static, but ever-dynamic. It is not conformity to some ideal norm, but the creation of an absolutely unique, entirely self-specific norm. Nor is it accomplished in a self-contained vacuum, but in relation to the world of personal experience.
We are called upon to emulate and aspire to Authentic Personhood. To do so is not to imagine being like someone else, but to apprehend the dynamic — creative and relational — that facilitates that transformation. The test of authenticity is integrity with respect to one's own particular expression of personhood.
The Authentic Person, moreover, has not "arrived", but is ever-evolving. Authenticity is ever-dynamic; if we can speak of possession, then this person is in possession of this dynamic, not of some imagined, fixed 'state of being'.
Yes, there are common, normative precipitants that manifest from this authenticity. Chief among these is freedom from the egoic identity, a presumption of a static, insular, and fixed self which must be protected from the transforming world at large. And this manifests as freedom from the fear of loss, there being nothing to lose, and freedom from the acquisitive desire for merit and name (thinking oneself and being thought to be someone special), there being no aspect of self requiring support. These are the signs of authenticity because they are also what make it possible.
Authenticity is always possible just as and where we are. No ideal is required. To be honestly engaged with the mess that we are, to be sincerely at work in the process of self-cultivation, is itself authenticity. Being human is authenticity, where that humanity realizes itself as self-creative and dynamic.
You can check out Scott's writings on Zhuangzi here.