An Etymological Dictionary of the German Language/Annotated/Zirbel

by Friedrich Kluge

Zirbel, feminine, in Zirbeldrüse, feminine. ‘pineal gland,’ from Middle High German zirbel-, in zirbelwint, ‘whirlwind'; allied to Middle High German zirben, ‘to move in a circle, whirl,’ Old High German zerben, Anglo-Saxon tearflian, ‘to turn.’ The Teutonic root tarb, ‘to whirl,’ cannot be traced farther back.