gordian knot: an intricate knot tied by Gordius, the king of Phrygia, and cut by the sword of Alexander the Great after he heard that whoever undid it would become ruler of Asia
knot: any of various fastenings formed by looping and tying a rope (or cord) upon itself or to another rope or to another object
cantor: the official of a synagogue who conducts the liturgical part of the service and sings or chants the prayers intended to be performed as solos