respectfully (in letter closings)
Honorific expression used after the addressee's name in formal letters, similar to 'Respectfully yours' or 'With respect'. Not used in everyday speech.
At the end of the letter, one writes 'Yamada Taro-sama, respectfully'.
private secretary (historical)
Original meaning referring to a personal secretary or attendant who handled correspondence for a high-ranking person. Now largely historical.
In the Edo period, feudal lords employed private secretaries to manage their correspondence.