Generate the answer for a given question. The question requires common knowledge of English. Make sure that the answer is in detail, long, consistent with the context, and requires general knowledge of English. To be less repetitive, please vary your language for each question. Give a proper explanation to answer, and if necessary, provide the definition of various terms. And conclude your answer if it's long. If you have used other resources (e.g., Merriam Webster's.) to answer the question, include citations in your answer. You don't need to paraphrase the context of your resources, but make sure that your answer is consistent and complete.

The synonym of trope is defined as metaphor, but there seem to be some other implications when using the word trope that metaphor does not have. Can anyone explain this simply and sensibly?.
The word trope has shot to prominence in the last couple of decades... And as this article points out, 'Trope is the New Meme', which I read in two ways. Use of the word itself has become a meme (pattern of behavior that spreads throughout a culture). But also, the meaning of the word has shifted for many people. To quote from that article... trope has to do with an agreed-upon narrative, an archetypal reading of a story or situation according to the simplest and most widely-held beliefs, a kind of narrative stereotype. Or, as the excellent site tvtropes puts it... tropes are devices and conventions that a writer can reasonably rely on as being present in the audience members' minds and expectations. I actually studied literature over 40 years ago, but I can't say I remember us using the word in the 'typical' dictionary sense as given by OED... A figure of speech which consists in the use of a word or phrase in a sense other than that which is proper to it; also, in casual use, a figure of speech; figurative language. So far as I'm concerned, if someone wants to use it like that, I'm not going to argue with them or their dictionaries. But most current usages are more in line with my first two definitions above. Here's how tvtropes knits the two definitions together... Merriam-Webster gives a definition of 'trope' as a 'figure of speech.' In storytelling, a trope is just that a conceptual figure of speech, a storytelling shorthand for a concept that the audience will recognize and understand instantly.

Let's imagine a hypothetical business: Mistake Corp. Mistake Corp makes a lot of mistakes, and as it turns out, the reason they make these mistakes is typically the same. 90% of the time Mistake Corp makes a mistake, it's because of misinformation. I suppose misinformation is the opposite of a linchpin for Mistake Corp. I'd like to be able to use the word like so: 'Misinformation is the [anti-linchpin] of Mistake Corp' What non-ambiguous word, other than 'anti-linchpin', can I use to describe something that is a frequent cause for mistakes to those who aren't as English-savvy?.
I'd say that misinformation is the pitfall for Mistake Corp. A hidden or unsuspected danger or difficulty: 'There are obvious pitfalls of such behavior, if it ever developed into a habit.' They indeed seem to fall in time and again; check the box for unsuspected...

Variation lock seems more accurate by mathematical definitions Edit(to give it more context) Hey, can you tell me the combination of your lockbox ? Why don't we say variation(or permutation)? The order matters in this case and combination is an unordered set of numbers.
Because most people are not mathematicians. I know that sounds like a flippant answer, but it's genuinely the answer. There are many words which have a more precise (or even different) meaning for specialists, and the fact is that these words simply have both meanings. The question 'Is a tomato a fruit or a vegetable?' is an all too familiar example: to a botanist, it's a fruit; to most of us, it's a vegetable. So the fact that mathematicians use 'combination' in a more restricted way is irrelevant to almost everybody who uses the locks.