Out of all the kanji in this haiku, I find 雷 (RAI, kaminari: thunder) the most intriguing. It looks so simple: rain (雨) over a rice field (田).
(Actually, that’s not the etymology. According to one scholar, 田 here doesn’t mean “rice field” but instead represents the complex shapes of the paths that lightning creates. And there used to be three 田 shapes in this character.)
Despite the visual simplicity, this kanji has some tricks up its sleeve. For instance, have you ever tried counting thunderclaps? It probably doesn’t have the same soporific effect as counting sheep; a bit too noisy for that, I think. And the payoff doesn’t happen for a long time. When you get to 100, you still have nothing but 100 literal thunderclaps:
百雷 (hyakurai: a hundred thunderclaps) 100 + thunder
But 100 squared? Now, you’ve got something:
万雷 (banrai: thunderous (applause)) 10,000 + thunder
I suppose this is the sound of 10,000 people “thundering” with their hands.
And if one thinks of thunderclaps as coming one after the other in an automatic succession, as if the thunderclaps had fallen into some conformist, groupthink mode, then you get a very nice metaphorical meaning:
雷同 (raidō: following blindly) thunder + same
On a literal level, it’s a little hard to imagine thunder as combining with fire, air, and water, but in compounds anything is possible:
雷火 (raika: fire caused by lightning) thunder + fire
Wait, don’t we want a kanji for “lightning” here? There is one—電—the same kanji that means “electricity” in so many words. But I suppose it would have been too confusing to use 電 in the compound above, perhaps suggesting an electrical fire. As it turns out, 雷 can also mean “lightning,” at least in its kun-yomi form, kaminari. Maybe that’s the case above, even though we have an on-yomi on our hands.
空雷 (kūrai: aerial torpedo) air + thunder
水雷 (suirai: torpedo, mine) water + thunder
Even a fish can combine with thunder! Check it out:
魚雷 (gyorai: torpedo) fish + thunder
OK, I have to admit that I don’t know what’s going on—that is, why there would be a connection between water or fish and torpedoes. And that’s partly because I hate thinking about weapons and war (which is kind of funny, because I’ve decided that my August presentation on samurai-related kanji at the Asian Art Museum will focus on weaponry). But Wikipedia rapidly fills me in, showing me that there really is an oceanic aspect to torpedoes:
The modern torpedo … is a self-propelled explosive projectile weapon, launched above or below the water surface, propelled underwater toward a target, and designed to detonate on contact or in proximity to a target. The term torpedo was originally used for a variety of devices, most of which would today be called mines. However, from World War I onwards, “torpedo” only applied to an underwater self-propelled missile. Torpedoes are also colloquially called “fish” or, in the German Navy, “Aale” (eng.:eels).
As long as we’re in marine mode, I’ve noticed at least two whale-fish words involving 雷:
雷雨 (raiu: thunderstorm) thunder + rain
雷電 (raiden: thunder and lightning) thunder + lightning
