O·pus De·i 
(ōpəs dāē, dā)
(ōpəs dāē, dā)n.
A Roman Catholic organization founded in 1928, composed of both clergy and lay members and dedicated to fostering Christian principles at all levels of society.
[New Latin Opus Deī, work of God : Latin opus, work + Latin Deī, genitive of Deus, God.]