ec·cle·si·ol·o·gy 
(ĭ-klē′zē-ŏlə-jē)
(ĭ-klē′zē-ŏlə-jē)n.
1. The branch of theology that is concerned with the nature, constitution, and functions of a church.
2. The study of ecclesiastical architecture and ornamentation.
[ECCLESI(A) + -LOGY.]
ec·cle′si·o·logi·cal (-ə-lŏjĭ-kəl) adj.