Which term describes the lateral displacement of a story relative to the base?

The term that describes the lateral displacement of a story relative to the base is known as "story displacement." This term specifically refers to the movement of a building's floor or story in relation to the lower levels or the foundation during events such as seismic activity or high winds. Understanding this concept is crucial in structural engineering and seismic design, as it directly affects the structural integrity and overall safety of a building.

The other terms provided do not accurately capture this specific definition. "Horizontal shift" is a more general term that could be used in various contexts but lacks the precise definition associated with the lateral displacement of a story. "Floor migration" implies a change in floor levels or elevation rather than lateral movement relative to the base. "Base movement" refers more to the movement of the foundation or ground itself, rather than the displacement of the stories above it. Thus, story displacement is the most appropriate and precise term for this context.