It's Humpty Dumpty who's to blame, you know.
Yes, that's right, the Humpty Dumpty of Through The Looking Glass. The one who said (probably with a little help from Lewis Carroll):
"When I use a word...it means just what I choose it to mean — neither more nor less"
which is in itself almost enough to make us give up and go home.
"Slithy means 'lithe and slimy' "
Humpty goes on
"You see it's like a portmanteau — there are two meanings packed up into one word."
Now a portmanteau, for anyone who knows a little French, is obviously some sort of a coat carrier. (In fact in France, though it was once a piece of luggage, nowadays a portemanteau is a coat rack.)
In English, however, portmanteau has kept the piece-of-luggage meaning and refers to a heavy case with a hinged lid, the sort of thing a pirate might keep his treasure in if he didn't happen to have an island handy to bury it. In Lewis Carroll's time portmanteaus (or portmanteaux) were divided into two compartments.
The only trouble is, of course, that a portmanteau word isn't divided into anything. It isn't even packed. It's more...squished.
We have smog (smoky fog) Spanglish (Spanish English) Oxbridge (Oxford and Cambridge universities) and spork (a spoon-shaped fork).
See? Definitely squished.
So as a name portmanteau is quite quite wrong.
And I don't think that anyone but Humpty Dumpty would have got away with it.
Sort Of Word To Use Today Even Though It's A Bit Silly: a portmanteau word. Portmanteau comes from the French porter, to carry, and manteau, cloak, from the Latin mantellum.