#kanji

Like many countries, Japan uses a 12-month calendar. The names are very simple. January is literally "Month one", February is "Month two", etc:

一月 = January

二月 = February

However, before the Meiji Restoration (mid-1800s) it was common to use an older 12-month system. These months’ names referenced the weather and the seasons (similar to the French Revolutionary calendar).

August is 葉月.

葉 = leaf/leaves

月 = month

So what does August have to do with leaves?

It is likely a reference to 紅葉, red autumn leaves, which many Japanese people admire, almost as much as the cherry blossom in spring.

Of course, the autumn leaf season is actually more likely to begin in September or October.