*imaginal*

a. [ L. imaginalis. ] 1. Characterized by imagination; imaginative; also, given to the use or rhetorical figures or imagins. [ 1913 Webster ]

2. (Zool.) Of or pertaining to an imago. [ 1913 Webster ]

Imaginal disks (Zool.), masses of hypodermic cells, carried by the larvæ of some insects after leaving the egg, from which masses the wings and legs of the adult are subsequently formed. [ 1913 Webster ]