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”.
Ancient Chinese mysticism (yijing, wuxing, daoism) have the concept of earth as either kūn (field, like of grass) or di (earth, like soil). I believe both are 地. This is in contrast to Heaven (tian) which is above. I believe both were conceived of as infinite parallel planes.
天地人 (tiān-dì-rén) are Heaven, Earth, and Human; and were sometimes seen as the 3 primal forces of reality.
Thanks for the further info! That 地 alone does follow the pattern of the other languages.
Your explanation gives Ricci’s odd calque a lot more sense - he’s using the old term, but highlighting that it’s a ball, not an infinite plane. As in, he was trying to be accurate to the sources, and he could only do it through that calque.
Even the term “planet” here is noisy, as it implies knowledge of an orb floating and/or spinning in space.
Maybe a better (less modern scientific) term in this case would be “world”, which could have been “what I have seen and have heard about, plus the regions beyond where dragons lie”, as an equivalent to “one, two, three, many”.
Fair point - notlahtlacōl. “World” does seem more accurate.
I wouldn’t be surprised if modern Nahuatl varieties used tlālticpactli to refer to the planet itself. (Still, my example is from Classical Nahuatl, so your correction is spot on.)
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.
Casually dropping Basque into your comment: +1
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”.
Ancient Chinese mysticism (yijing, wuxing, daoism) have the concept of earth as either kūn (field, like of grass) or di (earth, like soil). I believe both are 地. This is in contrast to Heaven (tian) which is above. I believe both were conceived of as infinite parallel planes.
天地人 (tiān-dì-rén) are Heaven, Earth, and Human; and were sometimes seen as the 3 primal forces of reality.
Thanks for the further info! That 地 alone does follow the pattern of the other languages.
Your explanation gives Ricci’s odd calque a lot more sense - he’s using the old term, but highlighting that it’s a ball, not an infinite plane. As in, he was trying to be accurate to the sources, and he could only do it through that calque.
Woah, that’s awesome! I had no idea about the etymology. Thanks for sharing!
Even the term “planet” here is noisy, as it implies knowledge of an orb floating and/or spinning in space.
Maybe a better (less modern scientific) term in this case would be “world”, which could have been “what I have seen and have heard about, plus the regions beyond where dragons lie”, as an equivalent to “one, two, three, many”.
Fair point - notlahtlacōl. “World” does seem more accurate.
I wouldn’t be surprised if modern Nahuatl varieties used tlālticpactli to refer to the planet itself. (Still, my example is from Classical Nahuatl, so your correction is spot on.)