Surely, Will37 - "it turned out to be something of which I had never before in my life heard."
True Pedantry must not be allowed to die out undefended!
I'm chagrined that the crafty sting in the tail of this otherwise soft, but witty, old puzzle (except for 26d) appears to have been well and truly outed by others - I was schadenfreudelich looking forward to a massacre at the hands of Mr Green and his elves (surely he must have a whole hi-ho of them) of complacent veteran solvers falling for the obvious - but wrong - option.