Maltz has revealed some words which I don't want to keep secret from you any longer. I'm sending them in individual messages to keep the subject line separated.

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The Klingon verb ghe' is the one most likely to be involved here.  It means "be transformed, transmuted, metamorphosed, totally altered." In context, if someone said maS Daghe'moH'a'? (literally "Are you transforming a moon?"), this would be understood to mean "Are you terraforming a moon?" If context isn't clear, then there'd have to be more verbiage: tera' chu' DachenmoHmeH, maS Daghe'moH'a'? "In order to create a new Earth, are you transforming a moon?") or maSDaq yInmeH Humanpu', 'oH Daghe'moH'a'? "In order that Humans live [be alive] on the moon, are you transforming it?" or yInvaD maS Daghe'moH'a'? "Are you transforming a moon to benefit life?" (clunky translation).

I assume that the word "field" in "terraforming field" refers to a energy field of some sort that causing the terraforming to happen (and not to a plot of land that's undergoing terraforming).  If so, the shortcut way to refer to that field would be ghe'chem; a longer way would be ghe'moHbogh HoSchem. But, as above, if context is lacking, there'd have to be some additional stuff to make the nature of the transformation clear.

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