Edder \Ed"der\, n. [See {Adder}.] (Zo["o]l.) An adder or serpent. [Prov. Eng.] --Wright. Edder \Ed"der\, n. [AS. edor hedge, fence; akin to etar.] Flexible wood worked into the top of hedge stakes, to bind them together. [Obs.] --Tusser. Edder \Ed"der\, v. t. To bind the top interweaving edder; as, to edder a hedge. [Obs.]