The newly minted word 'transgender' along with the variations 'transgendered', and 'transgenderism' is explored in terms of both definition, implication and value.
 

The word 'transsexual' is a composite word constructed from latin root terms, a basic standard of science and medicine, used for the purpose of permitting precise and exact definition. 
'trans', which means essentially 'to move across', and 'sex' which defines reproductive physical construction, are brought together to form the complete word "transsexual".
The parts clearly and exactly define the meaning of the term, which is to cross from one physical sex to another.

'Transgender' is a problematic term in that the strict definition of it would suggest changing from one gender to another, and this is paradoxical at best, and nonsensical at worst.
 

Sex is physical. Sex is the shape and function and form of physical organs of the body. Gender is a subset of basic identity, a mental and emotional moiety, without an easily defined physical existence. Although our identity, and therefore our gender, reside in the neurochemistry of our physical brains, it is impossible to point to the precise location of either or to quantify them in a purely physical way. Identity, and gender, are the abstract result of the complex interactions of a vast system, not a specific thing.

Gender is part of identity of self. An individual person possesses an individual identity, and that identity is defined by a set of describable qualities, one of which is gender. If a person were to have their gender changed, they would be also changing their core identity. A different identity, by definition, would mean a different person.

A change of gender would essentially mean the death, or annihilation, of one identity, one personality, and the replacement of that personality with a new one.  Since the new personality would be a new individual, it can be argued that no transition has occured...just a replacement, following the destruction of a previous state.

Since the term "trans" defines a "transition" (this word itself derived from the root), and such transition is contradictory to the term "transgender" itself, the term 'transgender' is essentially meaningless...a paradoxical word devoid of definition.
Unlike 'transsexual' which clearly defines a condition, 'transgender' is a null term.

Attempts have been made to play with the word and force meaning upon it. An example would be to suggest that it somehow represents 'the whole spectrum of gender expression', as in 'across gender', but this is not a valid interpretation of the latin roots. A proper term for this concept would be "pangender" or "pangenderism", which would in fact mean "all gender".

It is essentially inescapable that 'transgender' is a poorly crafted attempt at terminology.

It has been suggested that the value of the word "transgender" may lie in the fact that it is meaningless, so that it forms a comfortably vague label to unite various kinds of people who exist outside cultural gender definitions but who have little in common otherwise. To this end it is commonly used, and this unification may have benefit in terms of seeking political power to liberalize society, or to redress social injustice.

However, in confusing sex with gender, and in helping to make the terms interchangeable with each other in the vocabulary of many, the word undermines the ability to speak meaningfully about the very issues that are being defended. This is an unfortunate flaw with the use of the word.

There is little doubt, however, that the term is gaining increasing and widespread acceptance. It should be noted that many nonsense words regularly enter service in the English language, and become defined by the society that uses them, for language is constantly changing over time. It is indicative to some degree, of the degree of illiteracy in our culture.

The current accepted definition of "transgender" is as an all-inclusive term for all persons whose expression of gender is outside the current cultural expectations or norms.