kalsono

A plain word for a plain garment. Kalsono is underpants: the undergarment worn on the lower half of the body. It is clinical and neutral in Esperanto, the register of a packing list or a shop sign rather than a joke, and it should be used that way. Esperanto is a language with an unusually small stock of coy alternatives, which turns out to be a mercy.

It is singular. English pants, underpants and briefs are all plural, which trips learners up constantly. In Esperanto one garment is unu kalsono and two garments are du kalsonoj, exactly like pantalono at rank 1,212, which is likewise singular. Paro da kalsonoj means two of them, not one, so avoid it unless you mean it.

How wide the word is. It covers briefs, boxer shorts and long johns alike. If you need to be specific, the compounds do the work without a new root: mallonga kalsono for shorts, longa kalsono or varma kalsono for the winter sort, subkalsono in the rare case where you are wearing two. Kalsoneto is the small version and is the usual word for briefs.

Where it sits in the wardrobe. Vesto at 237 is any garment; subvesto is the underwear category as a whole; ĉemizo at 1,146 goes on top and subĉemizo under it; ŝtrumpo at 2,422 covers the leg; and tolaĵo at 2,251 is the whole lot once it is in the wash.