What does 誠に mean?
誠に is a Japanese adverb meaning “truly, sincerely” in English. It is written as 誠に in kanji, まことに in hiragana, and makotoni in romaji. This word is part of JLPT N1 vocabulary.
Example sentence
遅れまして、誠に申し訳ありません。
I'm awfully sorry that I was late.