I always tended to figure that it depends on what language you happen to be speaking at the time.
The older spacefaring societies in the Federation certainly would've had their own names for Earth, after all - and the Universal Translator, and its supporting technologies, are a thing. So, someone speaking Vulcan would use whatever their word for Earth was - and the translator would chew on that and then spit out the English 'Earth', and so on.
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"V, did you do something foolish?"
"Yes, and it was glorious."
The older spacefaring societies in the Federation certainly would've had their own names for Earth, after all - and the Universal Translator, and its supporting technologies, are a thing. So, someone speaking Vulcan would use whatever their word for Earth was - and the translator would chew on that and then spit out the English 'Earth', and so on.
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"V, did you do something foolish?"
"Yes, and it was glorious."