What is Dewhut?
1.
Literally: Do what, with a southern or redneck twang. Not really sure what purpose the "do" serves.
In relatively rural areas, it serves as a synomym for "pardon?" or "what?"
Everywhere else, it's used to show utter disbelief and even dismay.
Context in a (unnamed to protect the guilty) Richmond, VA office:
"Do you have change for a five?"
Response: "Dewhut?"
Context everywhere else:
"I haven't gotten laid in a year."
Response: "Dewhut???"
See
