Usage: 2 forms in 2 verses
Form Translated As     In Verse(s)
γραμματεύοντα acting as scribe LXX.Jer.52.25
γραμματεύειν to act as scribe LXX.1Chr.26.29

Liddell-Scott-Jones

γραμματεύω (grammateuō) to write G:V

γραμματεύω-εύω,

to be secretary, hold his office, [Refs 5th c.BC+]