Lewis & Short

Idistaviso or Idisiaviso [the latter form ex conj. Grimm; Germ. from Idisi, maiden, and Viso, meadow; cf. Grimm, Deutsche Mythol. p. 372 ed. II., qs. the maiden’s meadow; is approved by Nipperd. ad loc., and has been adopted in the text by Halm; the MS. form, explained as splendid meadow, from ancient Germ. id = nitens, the sup. of which is idista, Grimm, Gram. Einl. p. xlii, is retained by Ritter], a plain bordering on the Visurgis, (the modern Weser); perh. near the modern Minden, Tac. A. 2, 16.