means Cheerful and good-humored, the sort of warm, hearty merriment that fills a room.

from From Latin 'jovialis,' meaning 'of Jupiter,' through the old astrological belief that those born under the planet Jupiter — named for the king of the Roman gods — were blessed with a happy, expansive temperament. So the word literally carries the planet's supposed gift of good cheer, the same way 'mercurial,' 'saturnine,' and 'martial' all bottle a planet's mood.