Definition of "shortage"

The admirable smoothness of the riding also reflected the greatest credit on those who, despite the difficulties caused by the shortage of men and materials, have succeeded in maintaining the track in such first-class order.

1946 July and August, Cecil J. Allen, “British Locomotive Practice and Performance”, in Railway Magazine, page 213

The dawn of the oil age was fairly recent. Although the stuff was used to waterproof boats in the Middle East 6,000 years ago, extracting it in earnest began only in 1859 after an oil strike in Pennsylvania. […] It was used to make kerosene, the main fuel for artificial lighting after overfishing led to a shortage of whale blubber.

2013 August 3, “The future of oil: Yesterday’s fuel”, in The Economist‎, volume 408, number 8847, archived from the original on 18 December 2013