jovial: [16] Etymologically, jovial simply means ‘born under the influence of the planet Jupiter’. It comes via French from Italian gioviale, a derivative of Giove ‘Jupiter’, which itself goes back to the Latin stem Jov- (from which English also gets Jove [14], as in by Jove!). Jupiter was thought of as endowing those born under its sign with happiness, and so by extension jovial came to mean ‘jolly, good-humoured’. The word Jupiter [13] itself represents a Latin compound of Jov- and pater ‘father’.
