Meaning

noun a rare heavy polyvalent metallic element that resembles manganese chemically and is used in some alloys; is obtained as a by-product in refining molybdenum

noun ancient Egyptian sun god with the head of a hawk; a universal creator; he merged with the god Amen as Amen-Ra to become the king of the gods

noun the syllable naming the second (supertonic) note of any major scale in solmization

originFrom Glover's solmization, from Middle English re (“second degree or note of Guido of Arezzo's hexachordal scales”), Italian re in the solmization of Guido of Arezzo, from the first syllable of Latin resonāre (“made to resound”) in the lyrics of the scale-ascending hymn Ut queant laxis by Paulus Deacon.

Etymology from Wiktionary, CC BY-SA 3.0