valonia
Concise Oxford English Dictionary © 2008 Oxford University Press:
valonia /vaˈləʊnɪə/
▶noun the acorn cups of an evergreen oak (Quercus macrolepis), which yield a black dye and are used in tanning.
– origin C18: from Ital. vallonia, based on Gk balanos ‘acorn’.
'valonia' also found in these Oxford entries:

