When it comes to English the problem can be split into two: the origin of the word, and its usage to refer to the planet.
The origin of the word is actually well known - English “earth” comes from Proto-Germanic *erþō “ground, soil”, that in turn comes from Proto-Indo-European *h₁ér-teh₂. That *h₁ér- root pops up in plenty words referring to soil and land in IE languages; while that *-teh₂ nouns for states of being, so odds are that the word ultimately meant “the bare soil” or similar.
Now, the usage of the word for the planet gets trickier, since this metaphor - the whole/planet by the part/soil - pops up all the time. Even for non-Indo-European languages like:
Basque - “Lurra” Earth is simply “lur” soil with a determiner
Tatar - “Zemin” Earth, planet vs. “zemin” earth, soil
Greenlandic - “nuna” for both
The furthest from that that I’ve seen was Nahuatl calling the planet “tlalticpactl” over the land - but even then that “tlal[li]” at the start is land, soil.
The metaphor is so popular, but so popular, that it becomes hard to track where it originated - because it likely originated multiple times. I wouldn’t be surprised for example if English simply inherited it “as is”, as German “Erde” behaves the same. The same applies to the Romance languages with Latin “Terra”, they simply inherited the word with the double meaning and called it a day.
And as to why Earth has become the accepted term rather than ‘terra’, ‘orbis’ or some variant on ‘mundus’, well, that’s a tougher question to answer.
In English it’s simply because “Earth” is its native word. Other languages typically don’t use this word.
That ⟨地球⟩ is perhaps the only exception that we’re damn sure on how Earth got its name. The guy who coined the expression was a priest of the Papal States called Matteo Ricci, living in Ming around 1600. He did a living translating works back and forth between Chinese and Latin, and calqued that expression from Latin orbis terrarum - roughly “the globe of soils”, or “the ball of earths”.
Late because I only discovered it first now but this is quite interesting. When I first read this post my initial thought was also to investigate Basque and other language isolates, but by coincidence I just happened to stumble upon the Ainu (language isolate (according to popular consensus from what i can gather anyways) that’s native to Hokkaido and parts of the easternmost islands of Russia) word for The Earth while looking through wiktionary: aynumosir (アィヌモシㇼ) which roughly means “the land of the humans.” Compared to the Nahuatl example it also seems that the word for “land” (mosir (モシㇼ)) does not have much to do with the word for dirt/soil on its own and seems to more explicitly refer to land as in territory/country, meanwhile the word for dirt/soil would be “toy” (トィ). As far as I know this would be the word for The Earth that is the furthest removed from having with earth/soil to do. Additional fun fact is that the Ainu word for the equivalent of heaven is “kamuymosir” (カムイモシㇼ ) which roughly means “divine territory/country.”
That’s indeed really far from the “dirt” → “our planet” connection.
I dug a bit further into this matter and perhaps Ainu is not an exception. Perhaps - please take what I say with scepticism; I’m just hypothesising, nothing solid.
Meanings #2 and #3 might be the result of simple homophony, but I think that they’re related. And that the word モシㇼ/mosir is bimorphemic, with the second morpheme being “that” シㇼ/sir, that originally meant “soil” - otherwise it’s hard to explain how it evolved into “mountain” under meaning #3. With then トィ/toy displacing the “old” word, and becoming the main word for “dirt, mud, soil”.
Or perhaps it’s just an exception and my hypothesis is bullshit. Either way thank you for bringing this piece of info up.
Interesting hypothesis! It’s indeed likely this could be the case, it’s just unfortunate only one variant of Ainu remains and that it’s in quite a precarious position, but it’s fun to see different paths of how words picked up their meanings either way.
When it comes to English the problem can be split into two: the origin of the word, and its usage to refer to the planet.
The origin of the word is actually well known - English “earth” comes from Proto-Germanic *erþō “ground, soil”, that in turn comes from Proto-Indo-European *h₁ér-teh₂. That *h₁ér- root pops up in plenty words referring to soil and land in IE languages; while that *-teh₂ nouns for states of being, so odds are that the word ultimately meant “the bare soil” or similar.
Now, the usage of the word for the planet gets trickier, since this metaphor - the whole/planet by the part/soil - pops up all the time. Even for non-Indo-European languages like:
The furthest from that that I’ve seen was Nahuatl calling the planet “tlalticpactl” over the land - but even then that “tlal[li]” at the start is land, soil.
The metaphor is so popular, but so popular, that it becomes hard to track where it originated - because it likely originated multiple times. I wouldn’t be surprised for example if English simply inherited it “as is”, as German “Erde” behaves the same. The same applies to the Romance languages with Latin “Terra”, they simply inherited the word with the double meaning and called it a day.
In English it’s simply because “Earth” is its native word. Other languages typically don’t use this word.
Thank you!
You’re welcome!
In Chinese it’s 地球 which is basically “earth (as in dirt) ball”
That ⟨地球⟩ is perhaps the only exception that we’re damn sure on how Earth got its name. The guy who coined the expression was a priest of the Papal States called Matteo Ricci, living in Ming around 1600. He did a living translating works back and forth between Chinese and Latin, and calqued that expression from Latin orbis terrarum - roughly “the globe of soils”, or “the ball of earths”.
Woah, that’s awesome! I had no idea about the etymology. Thanks for sharing!
Late because I only discovered it first now but this is quite interesting. When I first read this post my initial thought was also to investigate Basque and other language isolates, but by coincidence I just happened to stumble upon the Ainu (language isolate (according to popular consensus from what i can gather anyways) that’s native to Hokkaido and parts of the easternmost islands of Russia) word for The Earth while looking through wiktionary: aynumosir (アィヌモシㇼ) which roughly means “the land of the humans.” Compared to the Nahuatl example it also seems that the word for “land” (mosir (モシㇼ)) does not have much to do with the word for dirt/soil on its own and seems to more explicitly refer to land as in territory/country, meanwhile the word for dirt/soil would be “toy” (トィ). As far as I know this would be the word for The Earth that is the furthest removed from having with earth/soil to do. Additional fun fact is that the Ainu word for the equivalent of heaven is “kamuymosir” (カムイモシㇼ ) which roughly means “divine territory/country.”
That’s indeed really far from the “dirt” → “our planet” connection.
I dug a bit further into this matter and perhaps Ainu is not an exception. Perhaps - please take what I say with scepticism; I’m just hypothesising, nothing solid.
Accordingly to this Ainu-English dictionary, the word sir / シリ on its own means
Meanings #2 and #3 might be the result of simple homophony, but I think that they’re related. And that the word モシㇼ/mosir is bimorphemic, with the second morpheme being “that” シㇼ/sir, that originally meant “soil” - otherwise it’s hard to explain how it evolved into “mountain” under meaning #3. With then トィ/toy displacing the “old” word, and becoming the main word for “dirt, mud, soil”.
Or perhaps it’s just an exception and my hypothesis is bullshit. Either way thank you for bringing this piece of info up.
Interesting hypothesis! It’s indeed likely this could be the case, it’s just unfortunate only one variant of Ainu remains and that it’s in quite a precarious position, but it’s fun to see different paths of how words picked up their meanings either way.