It's unknown of what his actual name is. TLK:SNA 책 are not 디즈니 creation but outsider written. Alex Simmons who wrote the first book of the set "A Tale Of Two Brothers" came up with Taka for Scar's name. Simmons never worked with 디즈니 and he had their permission to release the 책 only in USA. I could assume that Scar was jealous of Mufasa even before Simba was born. that's how he was behaving like he was in the film. as far as his scar goes it maybe that he gotten the scar when he was born when his mother cut him accidentally 의해 stepping on him 또는 he might of clawed himself 의해 accident from birth. since Scar is brown it can be possible that his name is Kahawia which means brown in Swahili. But Scar is just Scar in the film universe it's self no filmmaker has given him an actual name.