dislocation

ot noun

1. The act of displacing, or the state of being displaced.
2. The displacement of parts of rocks or portions of strata from the situation which they originally occupied. Slips, faults, and the like, are dislocations.
3. The act of dislocating, or putting out of joint; also, the condition of being thus displaced.
4. (materials) A linear defect in a crystal lattice. Because dislocations can shift within the crystal lattice, they tend to weaken the material, compared to a perfect crystal.