1: ἀκριβέστατος
(Strong's #196 — Adjective — akribestatos — ak-ree-bes'-ta-tos )

the superlative degree of akribes, "accurate, exact" (cp. akribos, see ACCURATELY and associated words there), occurs in Acts 26:5 , "the straitest (sect)," RV (AV, "most straitest").