The meaning of words

Words are signs, and the signifier is arbitrary.

'When I use a word,' Humpty Dumpty said, in rather a scornful tone, 'it means just what I choose it to mean — neither more nor less.'

'The question is,' said Alice, 'whether you can make words mean so many different things.'

'The question is,' said Humpty Dumpty, 'which is to be master — that's all.'

Through the looking glass, Lewis Carroll

I often struggle with defining words in my writing. Clear and unambiguous definitions might seem to be the goal, but unambiguous is difficult (I much prefer provisional).

Apropos some material for TU100 I've been working on recently, I had cause to write the follow in an email discussion

"...so if the words are used in different ways, why do I want to define them this way here
...am I saying this a formal technical definition of these words?
...and if so on what authority?"

"Actually no, that's not what I am doing
...I have some important concepts that I need labels for
...in the context of digital signatures, I have concepts that I am labelling 'authentication' and 'non repudiation'
...in the context of biometric data I have concepts that I am labelling 'verification' and 'identification'
...though in both contexts, it is not just me doing that, there is a precedent that this is the way these concepts are labelled
...so although in a sense this is a more precise formal definition of the words, it is not about the words, it is about the concepts I am using them for
...it is not 'this word has this precise technical meaning', it is 'this concept has a precise technical meaning and I am using this word for it'"

I was quite pleased with where that finished up.