An Etymological Dictionary of the German Language/Kater

by Friedrich Kluge

Kater, m., ‘tom-cat,’ from the equiv. MidHG. kater, katere, m., OHG. chataro, m.; the r of Kater appears to be a masc. suffix; comp. Morder and Mord, Tauber and Taube; Enter-ich and Ente?, Ganser and Gans?, &c., Comp. Katze.