perianth

From peri- +‎ -anth, thus "around the flower.", from French périanthe, from New Latin perianthium.

perianth (plural perianths)

1. (botany) The sterile parts of a flower; collectively, the sepals and petals (or tepals).
2. (botany, bryology) The sterile, tubelike tissue that surrounds the female reproductive structure in a leafy liverwort.
   • 1992, Rudolf M[athias] Schuster, The Hepaticae and Anthocerotae of North America: East of the Hundredth Meridian, volume V, New York, N.Y.: Columbia University Press, →ISBN, page 5:

     Archegonia are surrounded early in their development by the juvenile perianth, through the slender beak of which the elongated neck of the fertilized archegonium protrudes.

• perigone

• Perthian, triphane