also: かんせい
noun
Forgive me for dispensing with the preliminaries, but I hasten to inform you that ...
A formal, old-fashioned opening phrase used in brief letters to skip customary seasonal greetings and get straight to the point. Rare in modern correspondence.
冠省、先日は大変お世話になりました。
Forgive me for dispensing with the preliminaries, but thank you very much for your help the other day.
冠省にて失礼いたしますが、早速用件を申し上げます。
I apologize for omitting the formal greetings, but I will get straight to the point.
From 冠 (かん, 'crown' or 'beginning') and 省 (しょう, 'omit'), literally 'omitting the beginning', referring to skipping the formal opening greetings in a letter.