Bluebottles

[Eve]

Why the name? Does anyone know?

[Quizmonster]

It may be connected with the fact that a 'bot' is a type of fly. The 'blue' part is simply a reference to the insect's colour. Putting the two together may conceivably have given rise to the idea of a 'blue bot' and - in the normal way of language-modification - that could have over time become 'bluebottle'.
That is a theory, at best, and I offer it as none of my etymological resources actually offers an explanation.

[B00]

Oooer @ QM having "etymological resources"

;-)

[Clanad]

...And, in November 1154 Nicholas Breakspear found himself unanimously elected Pope at Avignon. He took the name Adrian IV. Who, you say? Well, for the historically challenged, Nicholas Breakspear was the only Englishman ever to become Pope in Rome. He was born in the parish of Abbots Langley in approximately 1100 at Breakspear Farm, near Bedmond. So... what has this to do with the question? you rightfully ask... Seems Pope Adrian IV died choking on Calliphora vicina, the scientific name for the common Blubottle Fly. Finding nothing with which to expand or illuminate Q's speculative but well explained answer, I couldn't come away from the table without leaving some fodder for the Bluebottle...

[Quizmonster]

Did you like that, Boo? (I sound like Fred Dibnah - though without the Bolton accent - after the successful felling of a chimney-stack!)
I used the phrase you commented on because I have a veritable armoury of major actual and online dictionaries at my disposal, including the great-grand-daddy of them all, The Oxford English Dictionary.
None of them helps re 'bluebottle', sadly. Thus, my earlier offering is just a bit of "folk etymology" with me as the folk-person involved!

A nice historical addendum, C.

[B00]

Bless ya QM, all I got is some old Famous Five books and old telephone directories :-(

[Clanad]

Just a brief question Q... an armoury or an armoire? Still and all, a veritable treasure trove, I'm sure!

[Quizmonster]

Given that words may be used as 'weapons', C, I'll stick with 'armoury'. Certainly, my reference-books are not kept in a cupboard!
(I do hope I haven't missed an irony here!)