The word Korea originated from Korea's Kori(Koryo) dynasty. It was spread by Arabian merchants into Europe. But how was that possible?
Let's examine Kori ships:
According to Korisa(koryosa), Huge ships used by Wang Kon(877~943) called (de sun) were 16 bo(36.6m) long each side with weight exceding 250~280 tons.
That size matches with the Santa Maria used by Columbus in 15~16th Century!
This proves Kori's naval spremacy 5~600 years before Europe!
That's why Korisa also mentioned that even horses galloped above the ship!
On the Japanese official text of "Sougi"(g as in grape), you see Kori ships named "Gwa Sun" which had iron spikes on its front to ram down enemy ships. Reflecting that idea, we see that Turtle ships originated from Kori.
Also, Koreans had also deplyed a type of cannon named "Gwa po" and in "Sougi" the also mentioned the following verse:
[1019 Kori navy attacked with gunpowder]
Meaning that one of the top 4 Chinese invention of naval gunpowder was actually korean
Later, Turtle ships were 3 story based with gunpowder, which was possible due to Kori naval tecniques as well as gunpowder tecniques
Kori ships were mainly han sun() made by lee won shik. They were flat bottomed, and front and back had soft surface elevation effect. And becasue they placed boulders in bottom position recovery even from 15 degrees were possible. Also, they employed wooden pumps to take out water if it leaked.
Becasue of this naval supremacy, Kori was able to trade with Arabic nations, as well as its culture etc. The word Korea came from Kori.