Why isn't "previous month" an acceptable synonym for 先月?

Hi all

I was just doing my reviews when WaniKani rejected “previous month” as a valid synonym for 先月. I’m assuming it was an oversight, but if it isn’t, could someone please explain the reason as to why this is the case?



This might be a dialectical thing, but to me “last month” is the month before this month (i.e. the present day), whereas “previous month” is the month before some other time that I’ve specified earlier. For example, “They had hoped to open the bridge in May, but as work had only commenced in the previous month, it wasn’t finished yet.” (Which is to say, April.)

This concept of “previous month” is 前月 rather than 先月.


I see what you mean, but the way I see it, it’s not technically wrong to say that January was the previous month, even if it sounds a little strange in most contexts. I feel that it should at least say “That’s close, but not quite right” like it does with some terms like if you enter “to raise” for 上がる.


I agree, and the same logic applies to the pairing of 来月 (next month) and 翌月 (following month).

1 Like

What about the sentence

“Our sales increased over the last month”?

To me that means for the past 30 days, sales have gone up, not that they went up in January.

Not saying anyone is wrong, I’m agreeing that there’s more nuance than meets the eye.

There are overlapping use cases but that’s specifically why it’s important to distinguish between them I think. Same with 昨日/前日 and 明日/翌日

1 Like

The fact that “last month” can also mean other things, like “the final month”, is kind of tangential to whether the item 先月, which only means one specific “last month” out of the possible meanings of “last month”, should have “previous month” as a synonym, no?

1 Like

Last month, previous month, past month, a month ago, preceding month …

Just … add it as a synonym? :\

先月 isn’t how you would say those though…?

1 Like

Add a synonym. The nuances that may or may not exist between “last month” and “previous month” are not worth thinking too much about at such an early stage.

Also, it’s worth getting used to the fact that Japanese and English words don’t map 1:1 and that when WK (or an Anki deck or whatever) gives you a meaning, that’s just something to hold on to for memorisation.


I think it depends on whether you’re convinced by the explanations you’ve received so far. 先月 isn’t exactly ‘previous month’. If anything, it’s ‘the previous month (if we’re talking about this month)’. ‘Previous month’ is relative to the month being discussed. On the other hand, typically, ‘last month’ isn’t, and refers to the month prior to the one we’re currently in.

That being said, what I’d consider is this: do you feel this nuance is

  1. Important?
  2. Something you’ll remember and that you want to remember right now?

If it is, then you need to think about whether or not distinguishing ‘previous month’ and ‘last month’ is helpful for your retention. (I, for example, tend to use opposites and words that are similar but different to help remember nuances.) If, on the other hand, you’re not too concerned about the difference at this stage (and obviously, the translations we’re talking about do overlap), or you feel that ‘previous’ vs ‘last’ isn’t going to help you, then don’t bother and just add a synonym.

I personally think it’s important to be aware of the differences in nuance – i.e. to just know that there’s a difference, even if you don’t remember the details – but you’ll probably only really remember them once you see these words in the wild (and I can say for certain that I’ve heard 先月 many more times than 前月, so ‘which is which?’ gets cleared up pretty quickly).


I’m personally not convinced the nuance is all that relevant in this particular case; if I happen to see it in the wild, while I might associate it with “previous month” even though that isn’t exactly quite right, context should make it sufficiently clear that it can only mean “last month”. I suspect common sense would prevail; because it would not be relative to any particular time, it could only make sense for it to mean “last month”, although I do acknowledge that this nuance can be more of an issue if I’m the one who is speaking or writing.


This topic was automatically closed 365 days after the last reply. New replies are no longer allowed.