[from any of various machines' instruction sets]
1. vi. To move oneself to the left (right). To move out of the way.
2. imper. “Get out of my seat! You can shift to that empty one to the left (right).” Often used without the logical, or as left shift instead of shift left. Sometimes heard as LSH /lish/, from the PDP-10 instruction set. See Programmer's Cheer.