Lewis & Short

tŭnĭcŭla, ae, f. dim. [tunica].

  1. I. A little tunic, Plaut. Rud. 2, 6, 65; Turp. ap. Non. 538, 10; Varr. ib. 228, 27.
  2. II. A little coat, skin, or membrane: oculorum, Plin. 26, 12, 76, § 123; 29, 6, 38, § 124: stellionis, id. 30, 10, 27, § 88: hordei, Fest. s. v. gluma, p. 98 Müll.