Definition of tunic flower
: a low-growing perennial herb (Petrorhagia saxifraga synonym Tunica saxifraga) of the family Caryophyllaceae that has slender, grasslike stems with narrow leaves and small white or pale pink flowers
Note:
Tunic flower is native to usually rocky or alpine regions of central and southern Europe but has become naturalized in parts of Canada and the U.S. where it has escaped from cultivation.
— called also
coat flower, saxifrage pink 
