Lewis & Short

lăcūno, āvi, ātum, 1, v. a. [lacuna].

  1. * I. To hollow out, to fret or pit: lacunati tori, Plin. 15, 10, 9, § 35.
  2. II. To panel like a lacunar: summa lacunabant alterno murice conchae, Ov. M. 8, 564.