The dictionary did not prove you correct. It proved that you are using a word, which, in educated circles, is considered on par with "ain't." Once again, the listing ends with "Use Regardless instead." You are wrong, and it would be in your best interest to correct this error. It robs validity from your claims of advanced education, regardless of how adamantly you defend its use.
By the way, look out of your trailer door, I'll wave at you from across the park.