What was the half angel and half human called?

Half angels, or even more diluted sons of angels, were called niphilim. Although they are mentioned in The Bible they are usually translated as 'giants'-"There were giants on the Earth in those days". Which for a folklorist would be tantamount to translating pixies as trolls for instance. Surprisingly enough this more 'holy race' was actually responsible for the evil that caused Noah's flood. But quite a lot of this is Babylonian mythology.