🔼The name Gabbai in the Bible
The name Gabbai occurs only once in the Bible, but in a curious (or dubious, say some scholars) text: Nehemiah 11:8, which reads: ואחריו גבי סלי. This can mean that after "him" (presumably Sallu, see 11:7) came Gabbai-sallai, or Gabbi, Sallai and then some, or it means something different all together and we're clueless, which is not unthinkable.
🔼Etymology of the name Gabbai
The name Gabbai probably comes from the following root cluster:
For a meaning of the name Gabbai, NOBSE Study Bible Name List reads Tax Gatherer. Alfred Jones (Dictionary of Old Testament Proper Names) reads An Exactor Of Tribute. BDB Theological Dictionary lists the name Gabbai under the verb גבב and notes that the word גבי in the Talmud means a tax-gatherer.