Extended Strong's Greek Lexicon (Abbott-Smith based)
ringleader
Usage: πρωτοστάτης, -ου, ὁ (πρῶτος, ἵστημι) [in LXX: Job.15:24 AB * ;] prop., of soldiers, one who stands first, one in the front rank (Thuc., Xen.); hence, metaphorically, a leader: Act.24:5.† (AS)