(Really, it goes backwards to the movement of the solar accretion disk… and beyond as well.)

（大）風が吹けば桶屋が儲かる
((Oo)kaze ga fukeba okeya ga moukaru;
“When the (strong) wind blows, bucket-makers prosper.”)

Definition:

A well-known saying that refers to unintended consequences or unexpected ripple effects (Rube Goldberg effects, perhaps) of a situation or event. If a strong wind blows, (the Japanese believed), blowing dust and junk would fly into people’s eyes and blind them. A common way for blind people to make a living was to play the shamisen, so shamisen schools would be filled with new students. Shamisen are traditionally covered with cat-skin (!), so the cat population would decrease. This would allow the population of vermin such as mice and rats, to increase. Since these chew holes in buckets, bucket-makers would see an uptick in business and become wealthier – on money ultimately blown into their pockets, so to speak, by that strong wind.

Breakdown:

This kotowaza comprises two clauses, so we’ll do each of those, in order, from right to left.

The first clause’s verb is 吹く (fuku), “to blow,” in hypothetical form. The subject-marker particle が (ga) connects it to the noun 風 (kaze), or in some versions of the saying, 大風 (ookaze) – “wind” and “gale,” respectively.

The second clause’s verb is 儲かる (moukaru), “to be profitable,” in sentence-final form. Again the subject-marker particle が connects verb to noun, and in this case the noun is 桶屋 (okeya), where 屋 (ya), literally “roof,” indicates a maker and seller of something, and 桶 (oke) are round wooden vessels like buckets, barrels, and tubs.

Notes:

It seems that the regular-wind (kaze) version of this saying is more common than the “great wind” (ookaze) version. I would have used this saying for ka, then, except I’d already selected the ka entry in the series. Look forward to that, next week!

Example sentence:

「昨夜いっぱいセルフィーを撮ったせいで、新しい傘を三本買わないといけない…　って、大風が吹けば桶屋が儲かるだね」

(“Sakuya ippai serufii wo totta sei de, atarashii kasa wo sanbon kawanai to ikenai… ‘tte, ookaze ga fukeba okeya ga moukaru da ne.”)

[“Because I took a lot of selfies last night, now I have to buy three new umbrellas… there’s a ‘for want of a nail‘ for you.”]