"slaughter of birds," 1834, from Latin avis "bird" (from PIE root *awi- "bird") + -cide.

"care and breeding of birds in domestication or captivity," 1876, from French aviculture, from Latin avis "bird" (from PIE root *awi- "bird") + cultura "cultivation" (see culture (n.)). Related: Aviculturist.

"bird-shaped, resembling a bird," 1885, from Latin avis "bird" (from PIE root *awi- "bird") + -form.

U.S. car rental company, according to company history founded 1946 at Willow Run Airport in Detroit by U.S. businessman Warren Avis and named for him.

1610s, "a calling away from one's occupation;" 1640s, "that which calls one away from one's proper business," from Latin avocationem (nominative avocatio) "a calling away, distraction, diversion," noun of action from past-participle stem of avocare "to call off, call away," from ab "off, away from" (see ab-) + vocare "to call," which is related to vox (genitive vocis) "voice" (from PIE root *wekw- "to speak"). Commonly, but improperly, "one's regular business, vocation" (1660s). Earlier (1520s) in a legalistic sense "calling to a higher court."

But yield who will to their separation,

My object in living is to unite

My avocation and my vocation

As my two eyes make one in sight.

[Frost, "Two Tramps in Mud Time"]