August 2025, April 2026
I was not prepared for the intense heat of Tokyo in August. It sees your jetlag as you step out of the airpot, doubles it, and laughs at your disorientation all the way to the train station where you will get lost just trying to find the exit. So it is undoubtedly apt that Japan recently unveiled the new word kokushobi for days that reach 40C or above, based on the word koku meaning harsh or cruel. “Cruelly hot weather” suggests an animus, a vindictiveness, a weather that has got personal.
This word was introduced by Japan’s Meteorological Agency, after running an online survey allowing votes on 13 different options. A non-linguistic agency determining language, with a democratic component no less? The dictionary committee of the Académie Française would be up in arms.
This also raises the question, what are the other words? There is a very orderly, very Japanese scale here:
natsubi - for days reaching 25C or higher
manatsubi - for days reaching 30C or higher
mōshobi - for days reaching 35C or higher
There is also the verb natsumeku for when it is starting to feel like summer, literally to become like (meku) summer (natsu). That’s one of my favourite seasonal transitions, full of hope, but often delayed in the UK where false dawns get interrupted by a week of rain and temperatures dropping. All of which means I don’t have much use for the word natsubate, for summer fatigue, as long as the weather doesn’t become cruel.