6 letters · 9 points in Scrabble
origindog + -er but using this suffix playfully in a way it is not normally used; essentially just a nonsense substitution of syllable -er where the diminutive suffixes -o or -ie or -y would normally stand, while also facetiously construable as the agent noun for being a dog, if to dog meaning to be a dog were a unitary English verb: thus, the agent noun would denote one who exhibits dogness. More at…
Etymology from Wiktionary, CC BY-SA 3.0