Entry 3 senses · 2 variants Webster, 1913 Inseam · In·seam · IPA /ˈɪnsiːm/ v. t. n. 01 v. t. To impress or mark with a seam or cicatrix. imp. & p. p. Inseamed; p. pr. & vb. n. Inseaming 1. To impress or mark with a seam or cicatrix. 02 n. An inside seam of an article of clothing; especially, the seam that runs from the crotch of a trouser leg down to the bottom. 1. An inside seam of an article of clothing; especially, the seam that runs from the crotch of a trouser leg down to the bottom. 2. The length of the inseam of a trouser leg.