ligature (n.)

c. 1400, "something used in tying or binding," from Middle French ligature "a binding" (14c.), from Late Latin ligatura "a band," from Latin ligatus, past participle of ligare "to bind" (from PIE root *leig- "to tie, bind"). In modern musical notation, "group of notes slurred together," from 1590s; of letters joined in printing or writing from 1690s.