What is "Jai Dam" in Thai?
Literally I take it to mean 'heart black' but am not sure what that means to a Thai person exactly.
Is "Jai Rohn"-hot headed and "Jai Dee"-kind?

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Answer

Aloha ha ha ha .......Jai Dam is used when someone is being cold.

Answer

sawaddee ka, Jai Dam means unsympathetic, pitiless, selfish, wicked, mean, merciless. 
Actually, Thai people use this word,, when you would like someone help you something but she or he refuse to help you without good reasonable...(kao jai mai ka? Do you get it?) 

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