Jackass \Jack"ass`\, n. [2d jack + ass.]

1. The male ass; a donkey.

2. A conceited dolt; a perverse blockhead.

Jackass bark (Naut.), a three-masted vessel, with only the foremast square-rigged; a barkentine.

Jackass deer (Zo["o]l.), the koba.

Jackass hare, Jackass rabbit (Zo["o]l.). See Jack rabbit, under 2d Jack, n.

Jackass penguin (Zo["o]l.), any species of penguin of the genus Spheniscus, of which several are known. One species (S. demersus) inhabits the islands near the Cape of Good Hope; another (S. Magellanicus) is found at the Falkland Islands. They make a noise like the braying of an ass; -- hence the name.

Laughing jackass. (Zo["o]l.) See under Laughing.

Source: Webster's Revised Unabridged Dictionary (1913)