deficiency

plural deficiencies

1. uncountableInadequacy or incompleteness.

   The face which emerged was not reassuring.[…]. He was not a mongol but there was a deficiency of a sort there, and it was not made more pretty by a latter-day hair cut which involved eccentrically long elf-locks and oiled black curls.

   1963, Margery Allingham, chapter 17, in The China Governess: A Mystery, London: Chatto & Windus, →OCLC

   Synonyms: lack, lacking, lackingness, want · Antonyms: sufficiency, plenty, plentitude, plenitude, excess, surfeit

2. countableAn insufficiency, especially of something essential to health.

   1 more example

   One of academia’s deficiencies is that, though its lecture halls and graduate schools are replete with women, its higher echelons are not. Often, this is seen as a phenomenon specific to the sciences. … In fact, the disparity applies to the whole grove. Another report from 2006, by the American Association of University Professors, found the same ratio in the faculties of arts, humanities and social science, too.

   2013 August 31, “Promotion and self-promotion”, in The Economist, volume 408, number 8851

   Synonyms: lack, lacking, want, shortage · Antonyms: sufficiency, excess, surfeit

3. countableuncountablegeometryThe amount by which the number of double points on a curve is short of the maximum for curves of the same degree.
4. countableuncountablegeometryThe codimension of a linear system in the corresponding complete linear system.