ginger knob
vulgar derogatory A person, typically a man, with naturally red hair. Primarily heard in UK, Ireland.
necker's knob
dated A rounded knob mounted to the steering wheel of an automobile so that it may be steered with one hand. So called because the driver (typically male) is able to place his arm around his girlfriend or wife. My grandfather gave me his old Cadillac, which still had the necker's knob on the wheel from when he first started courting my grandmother.