In construction, a deficiency is an item or condition that is considered sub-standard or below minimum expectations, such as those mandated by either drawings or specifications or the building code or the fire code, and/or any combination of the foregoing. Deficiencies are routinely discussed and dealt with in construction site meetings.
In genetics, a genetic deletion is also called a Deficiency.

In Real estate law, a deficiency in the ability to pay off a debt is also called a deficiency judgment or deficiency judgement.