*musing here for a moment*
I wonder if the reason they went with "Ultra Woman" (I'm uncomfortable posting it this way and you'll hear why in a bit) is because the Superwoman is an evil character in the DC verse. Apparently she and "Ultraman" (yes you heard right) are part of the antimatter universe of the DC comics. Ultraman (who's alter ego is Clark Kent in that universe) is married to Superwoman. I wonder if the reason they chose it was for synchronicity (although if that was the case then she would be spelled "Ultrawoman" rather than "Ultra Woman".) I don't remember when the JLA graphic novel about the antimatter Earth 2 was released so I have no clue if that's part of the decision to name her "Ultra Woman."
CLARK: No. I'm just worried I'm a jinx.
JONATHAN: A jinx?
CLARK: Yeah. Let's face it, ever since she's known me, Lois's been kidnapped, frozen, pushed off buildings, almost stabbed, poisoned, buried alive and who knows what else, and it's all because of me.
-"Contact" (You're not her jinx, you're her blessing.)
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