A G-string (alternatively gee-string or gee string) is a type of thong underwear or swimsuit, a narrow piece of cloth, leather, or plastic, that covers or holds the genitals, passes between the buttocks, and is attached to a band around the hips, worn as swimwear or underwear mostly by women, but also by men. 

The two terms G-string and thong are sometimes used interchangeably; however, technically they refer to different pieces of clothing. 


A g-string is sometimes worn on beaches. G-strings are also worn by some go-go dancers.