The Collaborative International Dictionary of English v.0.48:
Cementitious \Cem`en*ti"tious\, a. [L. caementitius pertaining to quarry stones. See Cement, n. ] Of the nature of cement. [R.] --Forsyth. [1913 Webster]WordNet (r) 3.0 (2006):
cementitious adj 1: like or relevant to or having the properties of cement; "the adhesion of cementitious materials"