Classification Rate

Ratio of correctly classified rows to the total number or rows.

For classification predictive models, it corresponds to the ratio of correctly classified rows to the total number of rows.
Example
A classification rate of 0.82 means that 82% of the rows in the training dataset are correctly classified by the predictive model.
Note
The classification rate is not very well adapted to unbalanced cases, when the target category is not very frequent. For example, if there is only 1% of the target category, it's very easy to have a very high classification rate. In such a case, check the Predictive Power or the Area Under the ROC Curve (AUC).