1753 Chambers Cycl. Supp.s.v. Leaf,Duplicato-ternatea Leaf, one consisting of leaves, which are themselves composed of three leaves each. 
1845 Lindley Sch. Bot. i. (1858) 9In like manner we have the terms bicrenate and bidentate, or rather duplicato-dentate. 
ORIGIN: from Latin  duplicatus : see duplicate  adjective & noun -o- 
duplicato-
combining form 
Etymology: probably from New Latin, from Latin duplicatus duplicate — more at duplicate 
 : doubly 
< duplicato-dentate >
< duplicato-dentate >