clever clogs
noun phrase (chiefly British and Australian)

- someone who shows that they are clever, in a way that annoys other people

Cambridge Dictionaries

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Remember the person in school who raised his/her hand every time the teacher asked the class a question? Or how about that neighbour who keeps telling you how to maintain your garden? Ever had a co-worker who won't let anyone else talk in a meeting? Ever met a stranger on a train who insisted on telling you everything you didn't want to know about his new mobile phone?

If you answered yes to any of these questions, then you already know what a clever clogs is.

In the 19th century people used the term "boots" instead of clogs (He's a clever boots!), as boots was a general term to describe a particular person (He's a shy boots, but you'll like him).

Clogs refer to various wooden or wooden-soled shoes, but it's not clear why they replaced boots in this expression. As with many words or phrases, someone on the planet decided it sounded better and started to use it, not knowing it would eventually become part of common speech.

A clever clogs is also referred to as "a clever Dick" and as with boots and clogs, there is no explanation as to why the name Dick is used, as opposed to John, George, Paul, or even Ringo. As Bruce Hornsby famously wrote in his same-named hit song, "That's just the way it is."

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SYNONYMS

wise guy, smart ass, know-it-all, smarty pants, wisenheimer, smart aleck, braggart, walking encyclopaedia

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Practice OWAD in a conversation:

"Many TV talk shows are just full of CLEVER CLOGS."