Hem tape refers to a kind of adhesive tape used for sewing or fixing the edges of fabric, like clothes or curtains, without actually sewing them. It helps in creating a neat, clean, and temporary hemline. Full definition
I've tried using hem tape before but it's never worked this well! (bravenewhome.com)
Then wrap that inch of hem tape and velvet ribbon at the bottom into the inside of the pant and secure it the same way as the rest, with heat. (papernstitchblog.com)