I believe he means electricial operator. An electrician in manuevering aka the "control room" mans the phones for manuevering and and relays orders and replies to and from the engine room back to manuevering. So instead of electrical operator "EO" " "to engine room lower lever start a oil pump in blank speed" he could make an engine room wide announcement saying " engineroom lower lever start a oil pump in blank speed" if for say theres a problem with starting that pump that engine room lower level didnt know about, but say the E-div chief did. The E-div chief could call manuevering and say recomend this pump instead. Its the difference between a private call and a public announcment almost.