Nephilim

(Hebrew נפלים) Translated in the Bible as “giants,” but actually derived from נפל, “abortion; fall; dud; to fail, to die, to be conquered.”

“There were giants [נפלים] in the earth in those days…” – Genesis 6:4

“The land, through which we have gone to search it, [is] a land that eateth up the inhabitants thereof; and all the people that we saw in it [are] men of a great stature. And there we saw the giants [נפלים], the sons of Anak, [which come] of the giants [נפלים]: and we were in our own sight as grasshoppers, and so we were in their sight.” – Numbers 13

The term Nephilim refers to fallen angels or masters, who were “giants among men” but fell, becoming demons. The Zohar describes five types of such beings.