נָבַב (nābab) is
a Hebrew verb
meaning hollow out. It appears
4 times
in 3 books of the Hebrew Bible
(Strong's H5014).
Also rendered
be hollow
Same Hebrew root (TWOT 1278)
Range of meaning (TWOT 1278)hollow out; pierce, be hollow, foolish; vain
Full entry: Brown-Driver-Briggs and Strong's
נָבַבverb: hollow out
Strong's H5014נָבַב: to pierce; to be hollow, or (figuratively) foolish KJV:hollow, vain.
Meanings: Brown-Driver-Briggs (1906) and Strong's Hebrew Dictionary (1890), public domain, via the Open Scriptures Hebrew Bible Project (CC BY 4.0). TWOT numbers for reference only.