Dean, aged 53, whose surname has not been disclosed, was last seen at about 8am on Saturday (September 7) near Heyford Hill.
Today (September 10), Thames Valley Police issued another appeal, urging people to call 999 if they see Dean.
Thames Valley Police believe he may have visited the Radley area, Littlemore and Rose Hill in recent days.
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He is described as being around 5ft 8ins tall, mixed race and bald with a grey beard.
He was last seen wearing earrings and dressed in a black jacket, trousers and work boots.
“We are urgently sharing our appeal to help locate Dean, aged 53, who was last seen in Berinsfield,” the appeal said.
“We believe he may have visited the Radley area and also Littlemore and Rose Hill in recent days.
“If you see him, please call us immediately on 999.”