訳(わけ)だFor that reason, No wonder, As you'd expect, Naturally, Thus, This is why

One of the most misunderstood words in Japanese is 訳(わけ). Of the many ways it can be translated, the most common are 'reason', 'cause', 'meaning', or 'conclusion'. Despite this, it may be beneficial to consider it almost identical to an equally versatile English word 'so'.

In all of its uses, わけ simply highlights the plain existence/determination of something in the same way that 'so' does in English. This can be seen in its most basic form in わけだ. A combination of わけ and the auxiliary verb だ.

わけだ will be used at the end of sentences, and is sometimes preceded by という. This use is often translated as 'for the reason of (A)', 'no wonder its (A)', or 'its (A), as you'd expect'. Realistically though, it just means 'it is so that it's (A)', or 'so it's (A)'.

Due to わけ being a noun, it will need to follow the attributive form of whatever word comes before it. As we can see 'so' and わけ have an extremely close pattern of nuances, ranging from 'because', all the way through to simple emphasis (like with 'naturally', and 'as you'd expect').

わけ may also be used in questions, implying that the speaker is trying to determine something that they have heard. わけだね 'so its (A) right?', and わけですか 'so is it that (A)?' are good examples of this.