from Wiktionary, Creative Commons Attribution/Share-Alike License.
superlativeform of uncouth: most uncouth.
Sorry, no etymologies found.
"I think he's the uncouthest of any person I ever saw."
The other self, tremulous, inconsequent, full of irresistible tenderness for suffering and weakness even in its uncouthest garb, said incessantly, "I could do no less.