LSJ
ακος, ὁ, keeper of receipts, PRev. Laws 10.2, al. (iii BC).
Liddell-Scott-Jones, Greek-English Lexicon (9th ed., 1940)
TBESG
keeper of receipts (MT)
Translators Brief lexicon of Extended Strongs for Greek based on Abbot-Smith, A Manual Greek Lexicon of the New Testament (1922) (=AS), with corrections and adapted by Tyndale Scholars