What does 호남 (湖南) literally mean?

 ANSWER: South of the Lake

The Sino-Korean word 호남 (湖南), or Honam, is another name for the region made up of both North and South Jeolla Provinces, but the word literally means "South of the Lake": 호 (湖) means "lake," and 남 (南) means "south." But to what lake is the word referring?

My Chinese character dictionary says that the lake was 벽골호 (碧骨湖), which literally means "Blue (碧) Bone (骨) Lake (湖)." It was a reservoir built during the time of Silla and was also called 벽골지 (碧骨池). It was located near Kimje City  (김제시) in North Jeolla Province, which at the time was part of the Baekje Kingdom (백제국 伯濟國). Today, the only thing that is left of the reservoir is part of its embankment, which is referred to as 벽골제 (碧骨堤) or "The Blue (碧) Bone (骨) Embankment (堤)." Some say that the embankment was actually a tidal sea wall.

But I am a little confused because I have also read that the 호남 (Honam) region was the region south of the Keum River (금강 錦江), which literally means "Silk (錦) River (江)." Apparently, an old name for the Keum River (금강 錦江) was 호강 (湖江), which literally means "Lake (湖) River (江). The river flows through part of North Jeolla Province (전라북도) and part of North Chungcheong Province (충청북도).

The founder of the Koryo Kingdom (고려), Taejo Wang Geon 태조 왕건 (~ 943), apparently did not trust people who lived south of the Keum River (금강) since he gave orders not to appoint anyone from that region to government positions. I guess there was some bad blood between Wang Geon and the people of Later Baekje (후백제), who lived in the Honam region.

When I was in the navy in Korea in 1978, I lived in a small 2-room apartment in the village outside the gate of Camp Humphreys. An old Korean woman who lived in the same compound stopped me one day and warned me, in Korean, not to trust anyone from Jeolla Province. It surprised me because it was out of the blue. So, even more than 1,000 years after the founding of the Koryo Kingdom, there are still Koreans who do not trust the people "South of the Lake."

From Dong-A's Prime Korean-English Dictionary

From 활용대옥편: Chinese Characters Dictionary