The word
pants is derived from
pantaloons, but I'm not totally comfortable with using
pants as a precedent!
When, in 2008, I eventually relented and accepted
pants and a number of other words, I
explained my reasoning like this:
Briefly, anyone who sees one of these words in the solution should readily bring to mind the usage in which it rarely drops its S to make a singular form.
This seems to apply to
pantaloons, if anything, more strongly than to some of the words I've accepted in the past. A
pantaloon can be a reference to a buffoon-like character in a pantomime, but that is very rarely used, although I assume Shakespeare had this sense in mind in his seven ages of man:
... And so he plays his part. The sixth age shifts
Into the lean and slipper’d pantaloon,
With spectacles on nose and pouch on side,
His youthful hose, well saved, a world too wide
For his shrunk shank; and his big manly voice,
Turning again toward childish treble, pipes
And whistles in his sound....
In reference to the clothing style, the singular
pantaloon is rarely used. One example was in a 2010 British Vogue article:
If you are looking to add some colour or a touch of summer whimsy to your wardrobe, a patterned pantaloon is the wild, offbeat luxurious option.
However, the headline of the article was "Printed Pantaloons". Writers sometimes also refer to "pantaloon-style trousers", as in a 2021 piece by Will Self about Extinction Rebellion, writing disparagingly of people in "pantaloon-style drawstring trousers".
All in all, it seems that singular
pantaloon is very rarely seen, so the more usual form,
pantaloons, should be allowed in future. And I feel the word is sufficiently well known to be treated as a common word.