What is a saiyan in Dragon Ball-Z

Saiyans are a different, superior species to humans.
When they turn to a super saiyan, their hair color changes to a bright golden yellow. in the exception of super saiyan 4 when eyes go black and hair goes Red, orange, or black.

a saiyan is a being born on planet vegeta or has a relative who is the saiyan's have a unique ability to transform into a giant ape known as great apes or oozarus which is done by looking at a full moon, the saiyan's also can change into a super saiyan 1, 2, 3 and 4 all of them have blonde hair except normal saiyan's which have brown and/or black hair and super saiyan 4's have the saiyans original saiyans form but have red hair all over their body and they don't have a shirt except for fusions who have a vest and super saiyan 4's have tails they are achieved through turning into golden great apes and a super saiyans eyes are green but super saiyan 3's and 4's have different colour eyes super saiyan 3's have a black centre of there eyes and super saiyan 4's have black centres and a yellow bit on the outside of their eyes a normal saiyan has black eyes and an oozaru has full red eyes no white
sorry for the huge definition.

*the saiyan race basically was wiped out except for Goku,Vegeta,(Broly and his father),(Nappa,Raditz),Tarble,and Goku and Vegeta's kids,grandkids,and great and great great grandkids

()= dead in first series