Definition of "deflection"

The next morning Oswald stopped short in the middle of his shaving, which in his case involved the most tortuous deflections and grimacings.

1918, H. G. Wells, Joan and Peter

The structure was examined and passed by the Board of Trade in February, 1890, after it had been tested with two trains of 50 loaded wagons, each hauled by two engines, and pushed by a third. The trains ran side by side, and their combined weight, including the six engines, was 1,800 tons. The deflections of the girders were precisely in accordance with the calculations of the engineers.

1950 March, H. A. Vallance, “On Foot Across the Forth Bridge”, in Railway Magazine, page 148