An Etymological Dictionary of the German Language/Annotated/Käfig

by Friedrich Kluge

Käfig, masculine and neuter, ‘cage, gaol,’ from Middle High German kęvje, masculine, feminine, and neuter, ‘cage (for wild animals and birds),’ also ‘prison’; the j of the Middle High German word became g (compare Ferge and Scherge). Old High German chęvia, feminine, is derived from Low Latin cávia, Latin cặvea, ‘birdcage’ (respecting High German f for Latin v, compare Pferd, Vers, and Verdikt), whence also Modern High German Kaue. Allied to the Romance words, Italian gabbia, gaggia, French cage (hence English cage), and Italian gabbiuolo, French geôle (English jail, gaol), ‘prison.’ Further, Bauer first obtained the meaning ‘cage’ in Middle High German.