Bikini panties are, by definition, low rise panties. With a waistband that sits below the naval and usually sits on the hips, low-rise bikinis are a perfect choice for today's low-rise jeans and skirts. In garment lingo, the rise is the measurement from the waistband to the first horizontal seam, which is usually where the crotch starts. The average rise on most panties is 6"". Low-rise panties will have a rise less than 5"".
Bikinis have other features that set them apart. Leg openings are usually high and the sides may be narrow as well. Rear coverage depends on the style. The low-rise bikini will not be visible above the waistband of today's very low-rise fashions. This style is also quite comfortable and surprisingly, a flattering choice for women with a bit of a tummy.