happiness (n.)youdaoicibaDictYouDict[happiness 词源字典]
1520s, "good fortune," from happy + -ness. Meaning "pleasant and contented mental state" is from 1590s. Phrase greatest happiness for the greatest number was in Francis Hutcheson (1725) but later was associated with Bentham.[happiness etymology, happiness origin, 英语词源]
PhilippinesyoudaoicibaDictYouDict
from Spanish Islas Filipinas, literally "the islands of Philip," named for Philip II, king of Spain. Related: Philippine.
unhappiness (n.)youdaoicibaDictYouDict
late 15c., "misfortune," from unhappy + -ness. Meaning "mental misery" is from 1722.