late 14c., "shun (someone), refrain from (something), have nothing to do with (an action, a scandal, etc.), escape, evade," from Anglo-French avoider "to clear out, withdraw (oneself)," partially Englished from Old French esvuidier "to empty out," from es- "out" (see ex-) + vuidier "to be empty," from voide "empty, vast, wide, hollow, waste," from Latin vocivos "unoccupied, vacant," related to vacare "be empty" (from PIE *wak-, extended form of root *eue- "to leave, abandon, give out").
In Middle English with a wide range of meanings now obsolete: "to empty, rid, take out, remove, discharge from the body, send away; eject or banish; destroy, erase; depart from or abandon, go away." Current sense corresponds to Old French eviter with which it perhaps was confused. Related: Avoided; avoiding.