Deficiency \De*fi"cien*cy\, n.; pl. Deficiencies. [See Deficient.]

The state of being deficient; inadequacy; want; failure; imperfection; shortcoming; defect. "A deficiency of blood." --Arbuthnot. [1913 Webster]

[Marlborough] was so miserably ignorant, that his deficiencies made him the ridicule of his contemporaries. --Buckle. [1913 Webster]

Deficiency of a curve (Geom.), the amount by which the number of double points on a curve is short of the maximum for curves of the same degree. [1913 Webster]

Source: The Collaborative International Dictionary of English v.0.48
 

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Source: Moby Thesaurus II by Grady Ward, 1.0
 

deficiency

Source: WordNet (r) 2.0
 

Deficiency \De*fi"cien*cy\, n.; pl. Deficiencies. [See Deficient.]

The state of being deficient; inadequacy; want; failure; imperfection; shortcoming; defect. ``A deficiency of blood.'' --Arbuthnot.

[Marlborough] was so miserably ignorant, that his deficiencies made him the ridicule of his contemporaries. --Buckle.

Deficiency of a curve (Geom.), the amount by which the number of double points on a curve is short of the maximum for curves of the same degree.

Source: Webster's Revised Unabridged Dictionary (1913)