Strong’s Hebrew
H5014 — nabab
The entry below is Strong’s own definition (1890, public domain), and every verse where the word occurs.
נָבַב
nabab — pronounced naw-bab
a primitive root; to pierce; to be hollow, or (figuratively) foolish:--hollow, vain.
4 occurrences in the KJV.
Exodus 27:8
Hollow with boards shalt thou make it: as it was shewed thee in the mount, so shall they make it.
Exodus 38:7
And he put the staves into the rings on the sides of the altar, to bear it withal; he made the altar hollow with boards.
Job 11:12
For vain men would be wise, though man be born like a wild ass’s colt.
Jeremiah 52:21
And concerning the pillars, the height of one pillar was eighteen cubits; and a fillet of twelve cubits did compass it; and the thickness thereof was four fingers: it was hollow.