The definition of a deficit occurs when there isn't a sufficient amount of money to cover all of the expenses and debts, or when you are not as good at something as you should be.
(noun)See deficit in Webster's New World College Dictionary
noun
Origin: L, there is lacking, 3d pers. sing., pres. indic., of deficere (see deficiency): from use as first word in inventory clauses
See deficit in American Heritage Dictionary 4
noun
Origin:
Origin: French déficit
Origin: , from Latin dēficit, it is lacking
Origin: , third person sing. present tense of dēficere, to fail, be lacking; see defect
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