Deficiency

Overview

A deficiency is a lack of something.

• In mathematics, a deficient number is a number n for which σ(n) < 2n.
• In medicine there are a variety of nutrient deficiencies:
  • Avitaminosis is a deficiency of vitamins.
  • Boron deficiency (medicine)
  • Chromium deficiency
  • Iron deficiency (medicine)
  • Iodine deficiency
  • Magnesium deficiency (medicine)
• In genetics, a genetic deletion is also called a deficiency.