"Surgical glue" refers to a special type of adhesive that is used by doctors during surgery to close wounds instead of traditional stitches or staples. It helps hold the edges of the wound together, allowing it to heal properly. Full definition
Then the incision is closed with sutures, usually absorbable on the inside with surgical glue on the outer layer of skin. (affordableanimalhospitalsilverlake.com)
Castrations usually have two small incisions near the top of the scrotum with purple surgical glue present — the scrotal sacs may swell almost to the pre-surgical size for up to 5 days after surgery and then gradually reduce to a fraction of their former size. (fvawl.org)