The French translation for "a pair of underpants" is un slip. There is 1 example of the French word for "a pair of underpants" being used.
MARVEL Spider-Man - Set of 3 Boy's Briefs 100% Cotton Oekotex
Buy French Connection men 3 pieces brand logo boxer briefs black
My $5 French Cut Underwear Is Just as Good as My $40 Pair
Tummy Control Shapewear Shapewear For Tummy Tummy Shaper Firm
Types of Underwear
Undergarments History Women's Pants, Drawers Underwear, Briefs
a pair of underpants in French
100% Knit Silk French Cut Underwear – Kim Allan Silk
TOF Paris - French Bikini - Heather Grey
french cut − 100% organic pima cotton underwear, oddobody
3 Pack French Connection Boxers
12 Types of Underwear and Panties for Women
MARVEL Spider-Man - Set of 3 Boy's Briefs 100% Cotton Oekotex
3 PAIR JOCKEY ELANCE WOMENS COTTON FRENCH CUT PANTIES SIZE 7
French Connection 3-Pack FCUK Dots Print Men's Underwear Boxer