In Celtic cultures, a bard is a professional story teller, verse-maker, music composer, oral historian and genealogist, employed by a patron (such as a monarch or chieftain) to commemorate one or more of the patron's ancestors and to praise the patron's own activities. With the decline of a living bardic tradition in the modern period, the term has loosened to mean a generic minstrel or author (especially a famous one). For example, William Shakespeare and Rabindranath Tagore are respectively known as "the Bard of Avon" (often simply "the Bard") and "the Bard of Bengal". In 16th-century Scotland, it turned into a derogatory term for an itinerant musician; nonetheless it was later romanticised by Sir Walter Scott (1771–1832). The English term bard is a loan word from the Celtic languages: Gaulish: bardo- ('bard, poet'), bard and bàrd ('bard, poet'), bardd ('singer, poet'), Middle Breton: barz ('minstrel'), Old Cornish: barth ('jester'). The ancient Gaulish *bardos is attested as bardus (sing.) in Latin and as (plur.) in Ancient Greek. It also appears as a stem in bardo-cucullus ('bard's hood'), bardo-magus ('field of the bard'), barditus (a song to fire soldiers), and in bardala ('crested lark', a singing bird). All of these terms come from the Proto-Celtic noun *bardos ('poet-singer, minstrel'), itself derived, with regular Celtic sound shift *gw > *b, from the Proto-Indo-European compound , which literally means 'praise-maker'. It is cognate with Sanskrit: ('calls, praise'), grātus ('grateful, pleasant, delightful'), gìrti ('praise'), and Armenian: ('raise voice'). In the words of the Oxford English Dictionary, the bards were an "ancient Celtic order of minstrel-poets, whose primary function appears to have been to compose and sing (usually to the harp) verses celebrating the achievements of chiefs and warriors, and who committed to verse historical and traditional facts, religious precepts, laws, genealogies, etc." In medieval Gaelic and Welsh society, a bard (Scottish and Irish Gaelic) or bardd (Welsh) was a professional poet, employed to compose elegies for his lord.