Obs. rare–1; only form 5 advencoun. [ad. med.L. adventiōn-em addition (Du Cange), n. of action, f. L. advenī-re to come to: see ADVENE.] An extrinsic addition.
c. 1400. Apol. for Loll., 55. Al kynd of syn, felony, and abhominacoun, and new aduencouns. And in þer aduencouns þey are filid [= defiled].
