"Thadook" is the the sound made by a car's tires as it it hits the small reflective square lane markers. Thadook driving is the technique used while under the influence or otherwise distracted to echo-locate your vector on the road. When one stops hearing the steady, repeative "thadook...thadook...thadook", one knows to brace for the impact.
I was thadooking down the road when it went silent and I think I went airborne. I was able to crawl from the wreckage with the dimebag and walk home.