Seraphim are a class of celestial beings, angels, in Judaism and Christianity. Literally "burning ones", the word is normally a synonym for snakes when used in the Hebrew bible, but they are mentioned in the Book of Isaiah as fiery six-winged beings attending on God. They appear again as celestial beings in an influential Hellenistic work, the Book of Enoch, and a little later in the Book of Revelation. They occupy the fifth of ten ranks of the hierarchy of angels in medieval and modern Judaism, and the highest rank in the Christian angelic hierarchy.

Isaiah's vision of seraphim in the Temple in Jerusalem is the sole instance in the Hebrew Bible of the word being used to describe celestial beings: there the winged "seraphim" attend God and have human attributes: "... I saw the Lord sitting upon a throne, high and lifted up; and His train filled the Hekhal (sanctuary). Above him stood the Seraphim; each had six wings; with two he covered his face, and with two he covered his feet, and with two he flew." (Isaiah 6:1-3) In Isaiah's vision the seraphim cry continually to each other, "Holy, holy, holy, is the Lord of hosts: the whole earth is full of His glory" (verses 2-3) before carrying out an act of purification for the prophet (verses 6-7). It is possible that these are winged snake-beings, but given that the word "seraphim" is not attached as an adjective or modifier to other snake-words ("nahash," etc.), as is the case in every other occurrence of the word, it is more probable that they are variants of the "fiery" lesser deities making up God's divine court.

Vampires, Ghosts and Demons also stem from this subject.