Entry 2 senses · 2 variants Webster, 1913 Birken · Birk·en · IPA v. t. a. 01 v. t. To whip with a birch or rod. 1. To whip with a birch or rod.[Obs.] 02 a. Birchen; as, birken groves. 1. Birchen; as, birken groves.