planet earth

[claymore]

When did this planet first become known as Earth,and who introduced the name?

[Quizmonster]

The earliest recorded use of the word in this way was in 1000 AD from the book of Genesis in a bible of the time by Aelfric.

[Quizmonster]

I should have added above that there are other biblical references from the same era. It depends to some extent whether one means earth as opposed to heaven and hell, the land as opposed to the sea or - as you say - the planet in general.
Basically, therefore, the source was one bible or another and the person who so used it was whoever had produced that particular version of it.

[Clanad]

Well.... as reluctant as I am to disagree with the estimable Q, I thnk perhaps I have a different take on the poster's actual intent...

If I'm correct (always debatable) claymore is asking when the "planet first became known as (the "English word") Earth." If that's the case, then our friends at "Online Etmology Dictionary" trace our modern word "Earth" thusly:

"earth"
O.E. eorþe "ground, soil, dry land," also used (along with middangeard) for "the (material) world" (as opposed to the heavens or the underworld), from P.Gmc. *ertho (cf. O.Fris. erthe "earth," O.S. ertha, O.N. jörð, M.Du. eerde, Du. aarde, O.H.G. erda, Ger. Erde, Goth. airþa), from PIE base *er- "earth, ground" (cf. M.Ir. -ert "earth"). The earth considered as a planet was so called from c.1400.

[Quizmonster]

As I said, C, there were various possible meanings attributed to the word a millennium ago, as indeed there still are. I'm perfectly happy to go with your source as regards the planet one.

[Andyvon]

However, the medieval concept of the world was different to that of today. Today, we recognise that Earth as a rocky planet orbiting the sun in space. It's one of countless planets, in countless solar systems, in billions of galaxies.

Medieval science considered the Earth differently though. The night sky was considered to be a series of glass shells which formed the 'roof' of the world. Stars, planets and comets were fixed to those moving shells and everything within was all that existed anywhere. All that Medieval man could see was everything that existed.

Surely therefore, wouldn't the 14th century term 'Earth' be used to signify the whole of existance itself?

[gen2]

So Andyvon. that would depend upon when humankind abandoned the concept of the geocentric universe.
That will be different for different nationalities, different religions and different individuals. I understand that even today, there are some that believe the earth is flat!
http://www.alaska.net.../Flatearthsociety.htm

[Andyvon]

Well, it was Galileo who risked his life to propse the heliocentric solar system Gen2, but that was two hundred years later. In the 14th century the modern concept of a planet orbiting one of 100 million+ stars in a galaxy was undreamed of. No other culture, such as the meso-Americans or Arabs, conceived the existance of the galaxy or universe either. I'm sure that first use of 'Earth' must have meant the whole of existance - land, seas, air, fire, people, animals and heavens.

[Quizmonster]

"Erthe that bitwixe is sett the sonne and hir." The 'hir' refers to the moon and the quote is from The Oxford English Dictionary under "earth considered as a sphere, orb or PLANET." It would seem that all three heavenly bodies were being seen as just that...individual heavenly bodies. In the case of the earth, the type of such a body is a planet. The quote is dated 1400 and hence, I am sure, the reference that Clanad made to that date earlier.
My mistake here yesterday was simply that I did not read far enough into the OED entry for the word, "earth"! If the language scholars at the OED feel that 1400 is the earliest date for earth = planet, then I am perfectly happy to go along with them.