The Evolution (and Ongoing Appeal) of Men’s Speedo-Style Spandex Briefs —plus why many guys eventually try bikinis, thongs, and G-strings 1) What we mean by “Speedo spandex briefs” Colloquially, “Speedo” gets used for any tight, brief men’s swimsuit. Technically, it’s a brand; the cut is a spandex/nylon brief with a low rise, elastic waistband, and …