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