Trousers (British English), slacks, or pants (American English) are an item of clothing worn from the waist to anywhere between the knees and the ankles, covering both legs separately (rather than with cloth extending across both legs as in robes, skirts, dresses and kilts).
"Knickers" derives from "knickerbockers," or "loose-fitting short pants gathered at the knee." Because the city's early Dutch settlers wore those pants, "New Yorkers" became known as "Knickerbockers."
Brits vs. Americans: Clothing Words - Anglophenia Ep 26
Why do British say knickers?
When men wore loose trousers for playing sports they were sometimes called knickerbockers. However, in Britain, women's underwear were soon called knickerbockers too. In the late 19th century the word was shortened to knickers.
As the name suggests, cheeky underwear features a narrower band of fabric across your backside than a typical bikini cut while providing more coverage than a thong. This style goes great lengths to accentuate the bum and the main feature to create a playful look that doesn't compromise on support.
And womens underwear became known as Knickers and it stuck. It's not only in Ireland, it is a common word usage in British English. It is a contraction of Knickerbockers. It was thought the loose Dutch Knickerbockers worn in New York looked like womens undergarments.
The prevailing theory is that the name comes from the fact that early versions of this undergarment were actually two separate legs that had to be “drawn” up and tied in place, hence why we still refer to underwear as “pairs” even though they are single garments now – “a pair of drawers”, “a pair of underwear.”
A bra, short for brassiere or brassière (US: /brəˈzɪər/, UK: /ˈbræsɪər/ or /ˈbræzɪər/; French: [bʁasjɛʁ]), is a form-fitting undergarment that is primarily used to support and cover a woman's breasts.
(ˈkɑrdɪgən ) noun. a sweater or jacket, usually knitted, that opens down the front and is usually collarless and long-sleeved. : also cardigan sweater (or jacket)
In American English, a vest is what the British call a waistcoat, while in British and Indian English, it is what Americans call an undershirt or tank top.
Underpants are a piece of underwear which have two holes to put your legs through and elastic around the top to hold them up round your waist or hips. In British English, underpants refers to only men's underwear, but in American English it refers to both men's and women's.
French knickers (also called tap pants in the United States) are a type of women's underwear or lingerie. The term is predominantly used in the United Kingdom (UK) and Australia to describe a style of underpants that look similar to a pair of shorts.
Plus fours are a version of knickers so called because the traditional style was four inches longer and had fuller legs. They were worn for outdoor activities and sports, and were popularized in the 1920s by the Duke of Windsor, who preferred them for his hunting and sporting excursions.
French knickers are typically loose-fitting with no elastic around the leg opening, making them perfect for everyday wear and also ridiculously comfortable. As many brands have developed their designs, not all French knickers will be the same.
In the United Kingdom, Ireland, South Africa, Malaysia, Singapore and occasionally in other Commonwealth countries such as Australia and New Zealand, panties may be referred to as "knickers", "undies", or simply "underwear".
High-Waisted Knickers: Whether or not you're looking for a pair of underwear with added compression or shaping capabilities, a high-waisted cut is ideal for a big tummy.
A blend of Organic Cotton & Hemp fibres make these high waisted undies soft and durable... perfect for lounging, dancing and sleeping. We know how hard it can be to find underwear that fits us well.
big-girl pants pl (plural only) (informal) Pull-up underwear worn by a girl during and after toilet training, as contrasted to the diapers worn during infancy. (informal, figuratively) A notional pair of trousers or underwear worn by a female when acting maturely.