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)