For you, it is certainly appropriate to simply call it "terraforming". The question is whether your aliens speak English. They most probably don't, and their word will almost certainly be a different one, having their own home world's name in it (in their own language).
Though when they communicate with you, presumably in a kind of universal language or such, you can still only call it "terraforming" since the audience does not speak universal-talk, and instead gets to read the English version.
Inalien... If only you could hear yourselves? "Human rights." Why the very name is racist. The Federation is no more than a 'homo sapiens' only club.