A corrected title is exactly what it sounds like, a fixed title. This is done when something incorrect is found and the owner, and holder of the title, applies for a new title with the corrected information. This most often refers to 1 of 3 things. 1. Actual ownership, when an error is made in processing.
2. Address
3. Mileage.
A miss read on a odometer is one people really make sure to correct, since that stuff can come back to haunt you and resale time.
Hope that helps.