Philadelphus lewisii (Lewis' mock-orange), of western North America
Pittosporum tobira, native to China, Japan, and Korea, and naturalized and cultivated elsewhere
Bursaria spinosa (Australian blackthorn)
especially, Philadelphus coronarius (sweet mock orange), widely cultivated
Styrax americanus (American snowbell)
Murraya paniculata (orange jessamine), a small tree ranging from East Asia to Australasia
Maclura pomifera (Osage orange), of North America
Pittosporum undulatum (sweet pittosporum), of Australia
Hence any of several flowering plants of the genus Philadelphus, such as now in the Western United States Philadelphus lewisii.
Any of several flowering plants, of the genus Syringa, such as the lilacs.