Peltate leaves are target shaped or shield like. Pictured is a peltate leaf of Indian cress.
"A, Shapes of bases of leaves; B, Peltate leaf of Tropaeolum. 1, heart-shaped; 2, arrow-shaped; 3, halberd-shaped."…
"Peltate.--Stalk fastened in the middle." -Newman, 1850
"Peltate, with the petiole inserted in the lamina, but not in the center of it."—Darby, 1855