You miswrote that Earth is mondiale in french, actually mondiale means more like world, globe or global depending upon how it is used. Use the word la Terre when refering to the proper name Earth. Although I agree with your assessment of the questioner and the answer in general - now who is the idiot? well maybe not complete idiot - just incorrect.
It’s a good idea if you post a link to the report your commenting on, just so everyone knows what you’re talking about.
Terre = earth (either dirt or the planet).
Monde = world. As far as I can tell, the semantic division between those two words is basically the same in French as in English. For example, the same distinction would be made between “saving the world” and “saving the earth.”
This actually kind of bugs me, as I feel like the actual question was a bit incorrectly phrased. What I thought when I read it was, are the names for earth, and the Earth, the same in other languages. Meaning that the word for the planet is basically the same word for soil.
As far as I know from the languages I know, most of the time it is.
English: earth, the Earth
German: die Erde on both accounts
Spanish: tierra, la tierra
So I’d actually like to know if it is actually the same word in all languages. Surely there must be a few that aren’t like this.
Actually, this has been discussed before on the board, more than once.
Do other languages call Earth “Earth”? December, 2006
More on “Do other languages call Earth ‘Earth’?” December, 2004
Do other languages call Earth “Earth”? September, 2004
French word for “Earth” August, 2003
Minor error in “Earth” translation January, 2003
As a guest, you wouldn’t know that, because you cannot search for old threads until you become a member. 
Earth in Hindi is called “dharti” which indeed means earth. Or rather earth means dharti. 
However, it’s also referred to as Pritvi, which is the Earth Goddess.
Every culture starts out with a geocentric model. What else would they call the-part-of-the-universe-that-isn’t-sky but “earth”?
Look, it’s nice to say that as a universal truth, but honestly, is it always the same? The original question to Cecil seemed quite idiotic, but I think it’s a valid question as I put it. I know three languages, and in all three they are the same, but I only know western languages. Maybe it’s different in other cultures? I think it’s a valid question.
Well, in Finnish the word for earth is maa, and the word for air is ilma, so not surprisingly the word for world is maailma.
In Thai, it’s “lok,” long O and rhymes with “poke.” Falling tone. It basically just means “world.”
Most languages distinguish between “world” and “earth”, “world” meaning the whole megillah, what God made, all there is, and “earth” meaning what everything that falls lands on, the place where people live, what the sun, moon, and stars revolve around.
I just asked the wife. She says no, it’s just “lok,” meaning “world.” I guess Earth as opposed to, say, Mars or Venus would simply be “this world.” But I’ve just shot a message off to a physics professor here of my acquaintance who speaks fluent Thai and specializes in planetary mechanics. He should know. I’ll get back to you.
Well, in Spanish we call the planet Tierra, the part of it that’s “not air and not sky and not water” either tierra firme or suelo… tierra without the firme also means (home)land and dirt floor; suelo also means “ground” and “the opposite of ceiling” but not soil… you guys don’t call this Planet Land nor Planet Dirt, do you?
Even when the words for “earth” and “Earth” coincide the meaning isn’t quite the same.
My physics-prof friend got back to me – he was upcountry – and yes, the word “lok” is used by Thai astronomers for “Earth” in lists of planets, even though the word also means “world.” So by itself in context, “lok” means “Earth,” but they also say “Mars is a ‘lok’.”