BBC Focus Magazine

[...]

ref Mega pixel photo of the blue morpho butterflys wing in the current mag poses a question for me, if all the other colours are absorbed and the only colour reflected is blue then surely blue is the only colour that isn't part of its makeup.

[M Paul Lloyd]

A very good point @@, and I recall having similar thoughts regarding coloured glass in as much as for it to allow the, say 'red' light through it must presumably absorb all the other wavelengths whilst clear glass allows most of it through unhindered, therefore the 'red' glass must in effect be every colour but red?
When it comes to opaque. solid colour we have black which absorbs all wavelengths and white (or a mirror) that reflects all wavelengths and so if something appears red or indeed blue is this an indication of what is being reflected or absorbed?

However, regardless of whether this an accurate observation or not, convention dictates that it is the colour that we see which we use to identify the colour in question.