Perianth

Look up perianth in Wiktionary, the free dictionary.

The term perianth has two similar but separate meanings in botany:

In flowering plants, the perianth is the outer, sterile whorls of a flower (see sepal, petal, and tepal).
In a liverwort, perianth is the sterile tubelike tissue that surrounds the female reproductive structure (or developing sporophyte).ca:Periant