Young Teen Girl In Tight Pants

Terminology
In the United Kingdom and Ireland most people use trousers or slacks as the general category term, whereas pants usually refers to underwear but is used, interchangeably with trousers, in some northern dialects. In Scotland, trousers are known as trews, which is the historic root of the word 'trousers'. Trousers are known as breeks in Scots.
In North America pants is the general category term (though Ambrose Bierce found the word "vulgar exceedingly" and recommended trousers), whereas trousers (sometimes slacks in Australia, the United States,) often more formally, to tailored garments with a waistband and (typically) belt-loops and a fly-front. For instance, informal elastic-waist knitted garments would be called pants, but not slacks.