Definition of seraphs:
(n) :
(post-biblical) A six-winged angel; one of the highest choir or order of angels in Christian angelology, ranked above cherubim, and below God.
(n) :
(biblical) A burning serpent, often winged, with human hands and sometimes feet; one of God's entourage. On Earth, they strike with burning poison; in Heaven, with burning coal. A description can be found at the beginning of Isaiah chapter 6.