Obs. rare. [Alteration of UNISON sb.: see UNI- and SOUND sb.3] A unison.
1763. Ann. Reg., Misc., 192/2. By dividing the musical notes into six, as nature directs, the unisound will fall on the seventh note. Ibid., 193/1. [The notes] i, j, s, d, are likewise unisounds to f, z, t, alike.
