Pants or underwear?

What do we call it in English?  Something that you wear under your dress?  Pants or underwear?

<em>But better would be:</em>

What are the things you wear under your dress called in English?  Pants or underwear?

<em>
</em>

<em>I am not an expert or women's undergarments, but I do know the general terms.</em>

<em>In the US, women's underwear refers to both bras and panties.  Panties is plural, you almost never say "a panty."  It is a "pair o panties."  In the UK, they are usually called "knickers."  Very thin nylon tights that you wear from toes to waist are called "pantyhose."  "Hose" comes from "hosiery which means stockings, so "pantyhose" combines the stckings and panties.  Most women wear panties under their pantyhose.</em>

<em>"underwear" is worn by both men and women. Men's underwear might be called undershorts, boxers, boxer shorts, or briefs.</em>

<em>"pants" are outer garments. They are called "trousers" in the UK.</em>

<em>Why do you ask?</em>

<em>Pants, trousers, panties, glasses, etc., even though they are one thing are almost always called "a pair of.." but you usually don't say my pair of pants, just, my pants...</em>

<em>
I </em>