So many mind-stimulating posts, that I do not know where to start.
Names to obscure one's real job - I prefer Chief Assistant to the Assistant Chief (which is how I describe MY job!)
Widgets are an example of a meaningless word that has been adopted and now has a real meaning (indeed, it injects somethingor other unnatural into my canned beer - it's enough to make me go back to home brewing! says he in disgust)
Surely words like "thingamajig" aren't nouns that describe nothing - they are describing everything - or, more properly, they have a universality that becomes specific only by reference to their context.
I have a vague feeling in the back of my head that whirligig is an archaic term for the smallish, dancing type of insect that hangs around damp areas and make nuisances of themselves at picnics. One can see how such a name could be transferred to all of the other things that we use it for.
