Notice, if you will, that this is A Definition of therianthropy.  There are many different definitions to be found.  This one in particular is very concise.  It is not a broad ranging definition and it may not cover what you have already been under the impression makes a therian.

Therianthropy: taken from the Greek roots Therios (beast) and Anthropos (man)

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What Makes a Therian?

A therianthrope, or were (as in werewolf) is a person who feels that they have some connection to an animal.  They might think they are an animal "inside" - in mind or spirit - or that they are part-animal in this way.  They may regard their mentality as being all animal, part animal, or an inseperable mix of animal and human.  They may feel that their soul is that of an animal.

Further to this feeling of being animal, a therianthrope also experiences "shifts".  This is where the intent of the alternative label "Were" comes from.  While a therian is completely human in body and thus cannot physically change into an animal, it is often common to feel other types of shift.  These most commonly include Mental Shifts and Phantom Shifts.  Mental shifts are times where the therian feels that their mindset and the way they are regarding the world has become very, or even entirely, animal.  A phantom shift is the equivalent of the phantom limbs feeling experienced by an amputee.  The therian feels as though the have phantom limbs or body parts not present in the human physique - for example, a tail.  These and other shifts will be examined later.

There are many other aspects of being therian which people feel or experience as individuals.  However, these two features are what distinguish someone as being a therianthrope, and by definition should be present in someone who is therian.

What Is Not A Therian?

Often it is said that no one can truly say whether someone is a therianthrope - they need to find this out for themselves.  This is partly true, but it is partly not.

Certainly, an invididual must look at whether they do really feel "animal", and whether their experiences are truly "shifts".  But if you experience neither of the above, or only part, then the definition therian does not fit you.  This is not to say that you are excluded from some kind of club, or that you don't have serious experiences you wish to address.  But it does mean that therianthrope is not a definition which could really be applied to you.  Some of the information may prove useful, but importantly, don't set out to define yourself.  Definitions and labels and categories that people fall under mean nothing.  It's most important to be yourself.

Explanations Of Therianthropy

Therianthropy does not have a true explanation, and although interesting to speculate on, no one will ever know for certain why therians experience the feelings that they do.

Commonly suggested explanations are both spiritual and mental; some believe it is a mental disorder, others believe that it could be the result of being animal in a past life, or having two or more souls inhabit the same body.

Most importantly, it must be accepted that regardless of whether the explanation is mental or spiritual, neither makes therianthropy any less real.  Therians do experience the feeling of living as a part-animal, that much is inescapable, and thus their experiences are valid.