Lewis & Short

ăvus (AVS, Inscr. Fabr. 389, also ăvŏs), i, m. [kindr. with Goth. avo, grandmother; old Norse, afi, grandfather; cf. Heb. [??], āb, father; Chald. [??], ἀββᾶ; and Engl. abbot], a grandfather, grandsire.

  1. I. Lit.: pater, avus, proavus, abavus, atavus, tritavus, Plaut. Pers. 1, 2, 5; so Ter. Phorm. 2, 3, 48; Cic. Cael. 14, 33; id. Mur. 7; Hor. S. 1, 6, 131; Vulg. Exod. 10, 6; cf. Dig. 38, 10, 1; 38, 10, 10; Isid. Orig. 9, 5, 9; 9, 6, 23.
    Also transf. to animals (cf. 1. avitus, II.), Verg. G. 4, 209.
  2. II. In gen.
    1. A. Ancestor, forefather, Hor. S. 1, 6, 3; Ov. F. 2, 30; id. H. 16 (15), 174; id. M. 9, 491; 15, 425; id. P. 4, 8, 18; Vulg. Gen. 28, 4 al.
    2. B. An old man, Albin. 2, 4.