paean (n.)

"hymn of praise, song of triumph;" in general use, "a loud and joyous song," 1590s, from Latin paean "hymn of deliverance, hymn to a help-giving god," from Greek paian "hymn, chant, hymn to Apollo," from Paian, Paiōn, a name of the god of healing; originally the physician of the gods (in Homer), later merged with Apollo; literally "one who touches" (i.e. "one who heals by a touch"), probably taken from a phrase or word at the beginning of the hymn, from paio "to touch, strike." The notion seems to be either a cry asking for aid in war or other trouble, or a giving thanks for aid received.