Knoppern

1 definition found

From The Collaborative International Dictionary of English v.0.48 [gcide]:

  Knoppern \Knop"pern\, n. [Cf. G. knopper. See {Knop}.] (Zool.)
     A kind of gall produced by a gallfly on the cup of an acorn,
     -- used in tanning and dyeing.
     [1913 Webster]