In Malayalam, the word "Vellam" or "Vallam" refers to water and so even a boat indirectly. "Kettu" refers to tying and therefore to the rope indirectly. The word Kettuvellam (or Kettu Vallam) jointly means this houseboat that is made of rope made out of Coconut bark.
The word Kerala comes from Kera Alam which means the big forest grove of Coconut trees. It is also called as Kairali in Malayalam. And so naturally we do see a lot of Coconut Grove in Kerala.
These houseboats were originally created to ferry the paddy produce to the land. In Allepey and nearby area, the local farmers use the backwater as a main source for irrigation. These paddy fields are kept filled with water for quite a lot of months before being irrigated and worked on. Slowly these boats have been used to transport people and mostly travelers on a overnight journey.
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