Old English fægen, fagen "glad, cheerful, happy, joyful, rejoicing," from a common Germanic root (cognates: Old Saxon fagan, Old Norse feginn "glad," Old High German faginon, Gothic faginon "to rejoice"), perhaps from PIE *pek- (1) "to make pretty." Often "glad" in a relative sense, "content to accept when something better is unobtainable." As an adverb, from c.1200. Related: Fainly.