1) Plant part 2) Plant structure 
[gastropod] clade Hypsogastropoda Volva is a genus of sea snails, specifically cowry allies or ovulids, marine gastropod molluscs in the family Ovulidae. Species within the genus Volva include: synonyms: == Further reading == ...[mycology] The volva is a mycological term to describe a cup-like structure at the base of a mushroom that is a remnant of the universal veil, or the remains of the peridium that encloses the immature fruit bodies of gasteroid fungi. This macrofeature is important in wild mushroom identification because it is an easily observed, taxonomical...
A cup-like structure at the base of a basidiocarp (in the Basidiomycetes). 
• (n.) A saclike envelope of certain fungi, which bursts open as the plant develops.
Vol'va noun [ Latin volva , vulva , covering.] (Botany) A saclike envelope of certain fungi, which bursts open as the plant develops. 
In botany, a volva is a cup-shaped structure that sheathes the base of the stalk of certain mushrooms.
[n] - cuplike structure around the base of the stalk of certain fungi
noun cuplike structure around the base of the stalk of certain fungi