Joyful, a.
Full of joy; having or causing joy; very glad; as, a joyful heart. "Joyful tidings." Shak. My soul shall be joyful in my God. Is. lxi. 10. Sad for their loss, but joyful of our life. Pope. -- Joy"ful*ly, adv. -- Joy"ful*ness, n.
Shades of meaning
Fernald has no entry of its own for joyful; he lists it under happy.
He lists it without comment; the entries above explain its neighbors.