Abbott-Smith Manual Greek Lexicon
πρωτοστάτης (G4414)
1 πρωτοστάτης , -ου, ὁ ( πρῶτος , ἵστημι ), [in LXX: Jb 15:24 AB*;] prop., of soldiers, one who stands first , one in the front rank (Thuc., Xen.); hence, metaph., a leader : Ac 24:5 .†
G. Abbott-Smith, A Manual Greek Lexicon of the New Testament (1922) — public domain