Dun \Dun\ (d[u^]n), v. t. & i. [imp. & p. p. {Dunned} (d[u^]nd); p. pr. & vb. n. {Dunning} (d[u^]n"n[i^]ng).] [AS. dyne noise, dynian to make a noise, or fr. Icel. dynr, duna, noise, thunder, duna to thunder; the same word as E. din. [root]74. See {Din}.] To ask or beset (e.g., a debtor), for payment; to urge importunately. [1913 Webster] Hath she sent so soon to dun? --Swift. [1913 Webster]