To · pi · ar · y (tö'pi-er'i), adj. [ L. topiarius, concerning an ornamental garden < topia (opera), ornamental gardening < Gr, topos, place], designating or of the art of trimming and training shrubs or trees into unnatural ornamental shapes. n. [ pl. TOPIARIES (-iz)], 1. Topiary art or work. 2. A topiary garden.