[in.ser.tion] n (1539) 1: something that is inserted: as a: the part of a muscle that inserts b: the mode or place of attachment of an organ or part c: embroidery or needlework inserted as ornament between two pieces of fabric d: a section of genetic material that is inserted into an existing gene sequence
2. a: the act or process of inserting b: the mutational process producing a genetic insertion -- in.ser.tion.al adj