Near "cation" in that same chemistry text you would be likely to come across "anion", another word which it might be hard to suss out: is it a two-syllable word with the stress on the first syllable, like "onion"?
Nope. They're both kinds of ions, and once you know that you can probably figure that they are pronounced "cat-ion" and "an-ion". Greek "kata-" means "down", and "ana-" means "up", so a cation is an ion that migrates downwards to the cathode, and an anion is one that migrates up to the anode. (Cation/cathode: anion/anode. See how easy? The "-ode" in "cathode" and "anode" is from Greek "hodos", "way"; you've also seen it in "electrode".)
I was reminded of all this because of this Slate article about a company called Cataphora, which gathers information which can be used to determine what employees might be up to. Its meaning in English--for it is an English word, a rhetorical term related to and alongside such others as "anaphora" and "diaphora"--is "to refer obliquely to something which will be referred to again later more specifically". In the sentence "She didn't know it at the time, but she was pregnant", the word "it" is a cataphora, because the word is explicated later (and is not a mere placeholder, because the sentence could have been written as "She didn't know she was pregnant at the time"). The construction can be used to build up a tiny bit of suspense: you could string together a series of clauses to keep the revelation for later. ("She didn't know it at the time, and she would have been horrified if she had known....") You can spin it out for quite a while, too, as in the lyrics to Elton John's "Your Song":
So excuse me forgetting but these things I do
You see I've forgotten if they're green or they're blue
Anyway the thing is what I really mean
Yours are the sweetest eyes I've ever seen
"They" in the second line is finally explained in the fourth line as "your eyes". Good, isn't it?
I feel as if "Cataphora" is not the best possible choice for a business name in this context, because the most usual meaning of "cata-" in Greek is "down", and sometimes "against". Couple that with "-phore", from Greek "pherein","to carry, to bear", and the innocuous meaning "to carry down [to a further point in the sentence]" can be interpreted as "to bear down [on]" or "to bear [witness] against". I'm sure it's just me, it's all in my head, but I find that a little unsettling.