Boyd’s Bible Dictionary:
(who lives on milk). Roman proconsul of Achaia, A. D. 53 (Acts 18:12-17).
Concise Bible Dictionary:
Roman proconsul of the province of Achaia, before whom Paul was accused; but who drove the Jews away, saying he would be no judge of words, and names, and of their law. Sosthenes was beaten before the judgment seat, but Gallio cared for none of these things (Acts 18:12,14,17). History states that Gallio was the brother of the philosopher Seneca, who speaks favorably of him. He was involved in the ruin of Seneca under Nero, and though he at first escaped, he afterward perished.
Strong’s Dictionary of Greek Words:
Meaning:
of Latin origin; Gallion (i.e. Gallio), a Roman officer
Potts’ Bible Proper Names:
Who lives on milk; giving suck; milky:―a Roman proconsul of Achaia, Acts 18:12. {Qui lactet}