used as combining form of medieval or modern Latin triangulātus, triangulateadj., in terms of Natural History denoting a combination of this with another form, as triangulato-ˈexcavate, triangulato-ˈovate, triangulato-subˈovate adjs.
ΚΠ
1849 J. D. DanaU.S. Exploring Exped.: Geol. (1850) App. i. 714 Very broad triangulato-ovate.
1852 J. D. DanaU.S. Exploring Exped.: Crustacea Pt. I 630 This segment is deeply triangulato-excavate posteriorly.