The Complete Guide to Men’s and Women’s Underwear

Underwear is the foundation of every outfit, offering comfort, support, and confidence throughout the day. Whether you’re reaching for your favourite loose-fit boxers, slipping into a pair of seamless briefs, or opting for bamboo trunk boxers for eco-friendly breathability, the right underwear plays a crucial role in how you feel and function—both in terms of physical ease and personal style.

From traditional cotton boxers and high-waisted briefs, to performance stretch boxers and organic bamboo underwear, this guide explores the full spectrum of underwear for men and women. We’ll also answer common questions like “What does the British call underwear?”, “Which type of underwear is better?” and “How should men’s underwear fit?”—offering practical insights for shoppers who care about fit, fabric, and function.

What Does the British Call Underwear?

In British English, "underwear" is the general term for garments worn beneath clothing, but more casual or specific terms are often used too. For women, "knickers" is the common term for underwear—ranging from full briefs to thongs—while men often refer to their underwear as "pants". While "pants" may cause confusion for Americans, in the UK it specifically means underpants.

Knickers, in British slang, can also be used light-heartedly or humorously. For instance, someone might say “Don’t get your knickers in a twist,” meaning don’t get upset or agitated. But when shopping or speaking about women’s underwear, knickers is a completely normal and widely used term.

Which Type of Underwear is Better?

There’s no single answer to this question—it depends on your lifestyle, body shape, and fabric preferences. For men, loose fit cotton boxers are ideal for lounging and sleeping, offering maximum breathability and freedom of movement. For more support and a closer fit, men’s stretch trunk boxers or fitted boxer briefs are better suited to everyday wear and physical activity. They reduce friction, stay in place, and offer structure under slimmer trousers.

For women, high-waisted briefs offer smoothing and security, while seamless underwear is ideal under tight-fitting outfits to avoid visible lines. Those with sensitive skin or an eco-conscious mindset often prefer bamboo briefs or organic cotton knickers, thanks to their soft, breathable, and naturally antibacterial properties.

Ultimately, the best type of underwear is the one that offers comfort, suits your needs, and fits your body correctly.

How Should Men’s Underwear Fit?

A well-fitted pair of men’s underwear should offer support without tightness or restriction. Whether you choose boxers, boxer briefs, or trunks, the waistband should sit snugly around the waist without digging in, and the leg openings should allow for movement without rolling or riding up.

If your underwear feels too tight, restricts movement, or causes discomfort after a few hours, it’s time to re-evaluate the style or size. Supportive men’s underwear like fitted trunks or stretch boxer briefs should hug the body comfortably and keep everything in place—especially during exercise or long days at work. Loose-fit boxers, meanwhile, should drape naturally and not cling, making them perfect for relaxation and sleep.