The kanji 訳 (わけ) means “translation” or “inference” and it can be used in a number of different ways to express or disaffirm a conclusion based on context or reason. Used in this way the word is very often written in hiragana.
|If you’re going to the gym more than three times per week then it would make sense to become a member.
|You look happy—that means you’ve passed the entrance exam, right?
|That’s why I came immediately.
Used in this way わけ actually has a slightly dated ring to it—the sort of language you might hear in a period drama or a samurai movie but not among younger friends. Couple it with the negative auxiliary verb, however, and we have a very common and useful phrase that can be used to stop the listener inferring the natural conclusion from the context. It’s closest English translation might be, “that doesn’t mean…”
|I studied Russian in university, but that doesn’t mean that I can speak fluently.
|I hold an accountancy qualification, but that doesn’t mean I’m good at maths.
わけではない is often heard with the phrase という. Used together the closest translation would be “that’s not to say…”
|That’s not to say it’s altogether bad.
|Having money doesn’t necessarily mean that you can be happy.
|I like gyoza, but that’s not to say that I want to eat it every day.
|I don’t mean to say that you must make a booking, but the restaurant is very popular so it might be better to give them a call beforehand.