un·con·for·mi·ty (ŭn'kən-fôr'mĭ-tē) n.
pl.un·con·for·mi·ties
Lack of conformity; nonconformity.
Geology A surface between successive strata representing a missing interval in the geologic record of time, and produced either by an interruption in deposition or by the erosion of depositionally continuous strata followed by renewed deposition.