That’s a really lame insult… unless the insulted one doesn’t know opeldok is, in which case it’s still just confusing.
В общем, похоже, опелдок это сокращенная форма оподельдока. Заодно и про оподельдок прочитал следующее:
word for word, it means “Oh you, Opodeldok Ivanovich!” Opodeldok was clearly not an actual Russian name, so I looked it up in my trusty Oxford dictionary (where it is listed under the more usual spelling оподельдок), and there it was—helpfully defined as “opodeldoc.” I let out a bellow of rage at the perfidy of the lexicographers who had taken the easy way out, refusing to give the user the slightest actual help, requiring an additional trip to the OED.
Ага, лексикографы они такие.
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