Nephilim, (Hebrew נפלים), present in the Old Testament (Torah), in various non-canonical books of Judaism and in ancient Christian writings, refers to a people created from the intersection of the “sons of God” and “daughters of men”, or giant who lived in the land of Canaan.
A similar term but with a different sound is used in the Book of Ezekiel 32:27 and refers to the warriors killed the Philistines.
In the Bible, the word Nephilim is often translated as “giants” or “Titans”, while in other translations you prefer to keep the term Nephilim.
The root thus most accepted is the Aramaic “naphil” which literally means “Giants“.
In Aramaic, there is the term AWS` [[Nephila], a name that identifies the constellation, Orion.
In this regard, many scholars argue that the root “nephil” refers to the constellation of Orion: The term “Nephilim” would be the plural of “nephila”. As the Bible says, the Giants were originally human beings. Other scholars, such as the American theologian Charles Ryrie Caldwell, argue that the etymological root of the Nephilim is “fall”, that fall on others, due to the men who were unexpectedly strong. In any case, they were not the offspring of those marriages where they would become heroes or famous men. Some versions speak of famous heroes, fallen warriors, or even fallen angels, and yet another translation might be those who have fallen since the name comes from the Semitic root nafal, which means fall. The early Christian apologists, such as Tertullian and especially Lattanzio welcomed the idea, this clearly in the Book of Enoch and the writings related to it, that the “sons of God”, the benei ha-Elohim were fallen angels, as also seems to allude the passage in Genesis.
Some commentators, finding objectionable or blasphemous the idea of copulation between angels and humans, have suggested more figurative interpretations of the Nephilim concept, proposing the idea that they were a progeny of possessed by demons.
In light of modern speculations on the stories of abductions, some have also speculated that it was an archaic description of a form of artificial insemination and genetic manipulation by aliens. In my point of view, the last hypothesis is that most accepted, I think that “they” have always been on the planet, and have helped to create fortifications and buildings megaliths with humans. In the past were giants and humans worshiped them as Gods.