underwear: what the term actually means
The word appears on a lot of underwear packaging, but it covers a range of very different constructions. Some styles are genuinely knitted in one piece with no seams at all. Others have the side seams cut away and the edges bonded or folded instead. The difference matters for how the piece feels and how long it lasts.
Circular-knit construction
True underwear is made on a circular loom, which knits the fabric in a tube shape. The piece is shaped during the knitting process itself, so there are no seams to cut and join. The result is a smooth surface on every side, including the hip, which is where most visible lines appear under fitted clothes.
This is the construction we use for the Brief and High-Waist Brief. The fabric is a 68% nylon, 32% cotton blend, which gives it enough stretch to hold its shape through the day while the cotton content keeps it breathable.
Bonded and laser-cut styles
The other common approach is to cut a standard fabric and bond or laser-cut the edges instead of sewing them. This removes the seam ridge but leaves a thin edge that can, over time, roll or fray. It is a less expensive process and works well for some applications, but it is not the same as circular knitting.
We do not use this construction in our range. The circular-knit approach costs more to produce but holds its shape better over repeated washing.
What to check when buying styles
Look at the gusset. Even on a circular-knit brief, the gusset is usually a separate piece sewn in, because it needs to be a different fabric (typically a softer, more breathable material). A well-made brief will have a flat, clean gusset seam that sits away from the body. On our briefs, the gusset is lined in organic cotton and the seam is kept as flat as possible.
Also check the waistband. A flat, fold-over knit waistband will not roll or dig in the way a standard cut elastic can. This is a detail that is easy to overlook in a product photo but makes a significant difference by the end of the day.
If you are trying styles for the first time, the 3-Pack Briefs is a low-commitment way to test the construction across a few washes before committing to more.