Some take the japanese dialect "Ojiisan", and add it to the japanese dialect "Tan" to combine it into a less formal dialect, which seems to be commonly used in Japan. Some dictionaries have decided to add the "modern dialect" Ujiitan to their registries, but although not all dictionaries have grown accustomed to it the word is perfectly acceptable throughout japanese culture. I learned this studying abroad, and Americans usually associate the word with a pokemon named Tony or something, which has a photoshopped face.
こんにちは私の名前はUjiitanです
by アナケチ3 :* February 04, 2019