Kangaroo court Katy bar the door Keep a wide berth Keen as mustard Keep body and soul together Keep schtum Keep a stiff upper lip Keep it under your hat Keep the ball rolling Keep up with the Joneses Keep your chin up Keep your hands clean Keep your nose clean Keep your nose to the grindstone Keep your pecker up Keep your powder dry Keepy-uppy Kettle of fish Khyber pass Kick the bucket Kick your heels Kickin' - Alive and Kilroy was here King James' Version of the Bible Kiss and tell Kiss me Hardy (The whole) kit and caboodle Knee-jerk reaction Knick-knack Knight in shining armour Knock back Knock off Knock on wood Know the ropes Know your onions Know which way the wind blows Knuckle down Knuckle under