An Etymological Dictionary of Astronomy and Astrophysics

1. To keep away from; keep clear of; shun.
   

   2. To prevent from happening (Dictionary.com). → abstain.

Etymology (EN): M.E. avoiden, from Anglo-French avoider “to clear out, withdraw (oneself),” from O.Fr. esvuidier “to empty out,” from es- “out,” → ex-, + vuidier “to be empty,” from voide “empty, vast, waste,” from L. vocivos “unoccupied, vacant,” vacare “be empty,” from PIE base *eue- “to leave, abandon, give out.”

Etymology (PE): Tosnidan, from Baluci tôsênag “avoid,” tusag “be quenched,” tôsaq “quench;” related to Pers. tohi “empty, void;” Mid.Pers. tuhig “empty;” Parthian tôšênitan “to empty;” cf. Pashto taš; Ormuri tusk; Waxi töš, təš; Sariqoli tīs; Skt. tucchá-, tucchyá- “empty;” L. tesqua “deserts;” O.Slav tušti “empty;” Russ. tošcij “meager.”