With the ongoing nuclear disaster in Japan, there has been a lot more occasion to hear nuclear-related vocabulary on the news. I’ve been learning new terms, and getting a scary refresher on others I hadn’t been entirely clear on before. I’ve now learned about containment vessels and control rods, and have also learned that a meltdown is so named because the fuel rods literally melt, a detail I’d been unclear on before. (Hey wow, unclear and nuclear are anagrams.)
On the American Dialect Society email list, a discussion has been going on about another nuclear-related term: fission. The question is: Is it pronounced more like fishin’ and mission, or like vision? That is, is it pronounced [fɪʃən], or [fɪʒən]? Before Sunday, I would have said [fɪʃən] (a lot like fishin’), no question, but that afternoon I heard Adam’s den leader pronounce it as [fɪʒən]. I dismissed it as one guy’s error, but judging from the ADS-L thread, the pronunciation is pretty common.
To me, it sounds like another case of contamination. We have a set of semantically related words; in this case, the pair fission and fusion. The words have something in common phonetically as well as semantically: their initial [f] and final [ən] syllable, not to mention the fact that both [ʃ] and [ʒ] that are similar acoustically. The words become even more alike phonetically when the [ʃ] in fission becomes an [ʒ] like the one in fusion. The different vowels in the words’ respective first syllables remain different from each other: one remaining phonetic difference to convey the semantic difference.
Why did fission become more like fusion and not the other way around, so that fusion ended up more like fuchsia and Confucian? Because fusion is the more familiar word, appearing in collocations such as fusion cuisine or jazz fusion. It’s also transparently related to the verb fuse. Although I see that fission also has biology- and anthropology-related meanings, the only time I ever hear it is in the context of nuclear stuff, and it has no related verb. Well, it does, but just not in English; the Latin verb source is findere.