| 1. | a shortcoming, fault, or imperfection: a defect in an argument; a defect in a machine. |
| 2. | lack or want, esp. of something essential to perfection or completeness; deficiency: a defect in hearing. |
| 3. | Also called crystal defect, lattice defect. Crystallography. a discontinuity in the lattice of a crystal caused by missing or extra atoms or ions, or by dislocations. |
| 4. | to desert a cause, country, etc., esp. in order to adopt another (often fol. by from or to): He defected from the U.S.S.R to the West. |

de·fect (dē'fěkt', dĭ-fěkt') n.
[Middle English, from Latin dēfectus, failure, want, from past participle of dēficere, to desert, be wanting : dē-, de- + facere, to do; see dhē- in Indo-European roots.] de·fec'tion n., de·fec'tor n. |
defect de·fect (dē'fěkt', dĭ-fěkt')
n.
A lack of or abnormality in something necessary for normal functioning; a deficiency or imperfection.
defect
bug
defect
imperfection in the regular geometrical arrangement of the atoms in a crystalline solid. These imperfections result from deformation of the solid, rapid cooling from high temperature, or high-energy radiation (X-rays or neutrons) striking the solid. Located at single points, along lines, or on whole surfaces in the solid, these defects influence its mechanical, electrical, and optical behaviour.
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