inseam

/ˈɪnsiːm/
noun
  1. The inner seam of a pant leg, running from the crotch to the bottom of the leg; also, the measurement of that length.
    • Pants with a 32-inch inseam are often hard to find in stores.
    • The tailor measured his inseam to make sure the jeans fit properly.
    • She checked the inseam of the trousers before buying them.