right-and-left \| ̷ ̷ ̷ ̷| ̷ ̷\adjective 1. a.: of or relating to the right and the left b.: designed for right and left feet or for right and left hands 2.: of, relating to, or constituting a screw, pipe coupling, coupling, turnbuckle, or sleeve nut formed with right-handed threads at one end and left-handed threads at the other