perianth
noun
peri·anth ˈper-ē-ˌan(t)th 
: the floral structure comprised of the calyx and corolla especially when the two whorls are fused see flower illustration
Example Sentences
Recent Examples on the Web The cup of the daffodil extends from radiating petals called a perianth. 
Adrian Higgins, Washington Post, 20 Sep. 2021 Dutch Master has a pale yellow perianth, and the trumpet is wide, richer in color and frilled. Adrian Higgins, Washington Post, 20 Sep. 2021
Adrian Higgins, Washington Post, 20 Sep. 2021 Dutch Master has a pale yellow perianth, and the trumpet is wide, richer in color and frilled. Adrian Higgins, Washington Post, 20 Sep. 2021 Word History
Etymology
New Latin perianthium, from peri- + Greek anthos flower — more at anthology
First Known Use
circa 1806, in the meaning defined above