How to Differentiate a Thong From a G-String. Although the two terms have become synonymous, there is a difference between a thong and a g-string. For the most part, a thong has wider material for the strip that runs along the bottom and rear quarters. It usually has a signature v-shaped design at the lower back, sometimes referred to as a "whale tail."
Differentiate a thong from a g-string by viewing the design and style of the panty or swimwear. Usually when an item is called a thong it's marketed for swim or active wear with a heavier material.
Spot a thong by its thicker construction and sturdy fabrics such as cotton and elastic bands. Others can be a bit dainty, like a standard g-string, but the thickness of the band is achieved with more layers of lace or other accents to create a thong look.
Note the reasons to wear a thong rather than a g-string. Most thongs are worn more for physical sports due to their wider range of material. You can typically wear a thong for an aerobics workout with tights underneath. A g-string is a more popular choice for lingerie, sleeping and dressing for a romantic night with a loved one.
Be aware that similar undergarments have been derived from the g-string and thong. A related style is called a v-string, which is made up of one piece of thin fabric that runs along the buttocks and becomes two strings, forming a small "v" just under the waistband.
Learn how to differentiate other variations of g-strings and thongs to better make the right purchase. A dance belt offers the same benefits of a thong, but is primarily used much like an athletic supporter by dancers seeking to move freely but with added security.