Rashi on Genesis 32:26/רש"י על בראשית ל״ב:כ״ו

1ויגע בכף ירכו HE TOUCHED THE HOLLOW OF HIS THIGH — The upper thigh-bone that is sunk in the hip is called כף because the flesh on it (on this bone) has the form of the hollow part of a pot-ladle (כף).

2ותקע AND WAS STRAINED — It was violently torn from its joint. Similar in meaning is (Jeremiah 6:8) “Lest My soul be alienated (תקע) from thee” — i.e. removed from thee; and in the Mishna, לקעקע בצתם, which means to remove violently (לשרש) their roots.