A "licensed contractor" refers to a professional who has obtained the necessary authorization or permission from the appropriate governing body to perform specific types of construction or contracting work. Full definition
For one all work must be done by licensed contractors, homeowner can do no work. (biggerpockets.com)
Make sure you're trading with licensed contractors for things like automotive or home repairs, or you will have little recourse if the work goes wrong. (gobankingrates.com)
Most states require licensed contractors for many types of repair work. (ppmbrevard.com)