BSN: CHERUB, CHERUBIM

CHERUB is singular
CHERUBIM is plural

Cherubim are first mentioned in the Bible at Gen 3:24 where they are stationed at the east of the garden of Eden along with “the flaming sword which turned every direction” to guard the way to the tree of life after God had driven Adam and Eve out of the garden.
They are next mentioned in the book of Exodus when God instructs Moses to have two replicas of them made of hammered gold to sit atop the ark of the covenant. The wings of the cherubim were to be spread upward while the cherubim faced each other. God would meet with Moses between them. Replicas of the cherubim were also to be woven into the tabernacle’s veil and curtains.
The cherubim imagery was continued in the transition of the ark of the covenant from the tabernacle (portable) to the temple (permanent).
In six different places in the Old Testament, God is said to be “enthroned above the cherubim” (2 Sam 6:2; 2 Kings 19:15; 1 Chr 13:6; Ps 80:1; 99:1; Is 37:16). Thus the architecture of the ark of the covenant is reflecting heavenly (spiritual) reality.

Related: Angels