BT Šab 108a(40) :אמ׳ יהא רעוא דתיפוק קרנא בעינך נפק ליה קרנא בעיניה‏ : he said: "may it be His will that a horn pop out on your eye," and a horn popped out on his eye
See the entire entry for qre/an, qarnā n.f. horn; angle