Trillium undulatum, commonly called painted trillium, painted lady (not to be confused with the painted lady butterfly), or trille ondulé in French, is a species of flowering plant in the bunchflower family Melanthiaceae. It is also known as smiling wake robin or striped wake-robin. The specific epithet undulatum means "wavy", which refers to the wavy edges of the flower petals. The plant is found from Ontario in the north to northern Georgia in the south and from Michigan in the west to Nova Scotia in the east.