Valonia
Valonia , noun
[Italian vallonia, vallonea, from NGr. balania`, balanidia`, the holm oak, bala`ni, balani`di, an acorn, Greek ba`lanos.]
1.
The acorn cup of two kinds of oak (Quercus macrolepis, and Quercus vallonea) found in Eastern Europe. It contains an abundance of tannin, and is much used by tanners and dyers.
2.
(Botany) A genus of marine green algae, in which the whole frond consists of a single oval or cylindrical cell, often an inch in length.