your letter; your esteemed letter
Formal honorific term used to refer respectfully to another person's letter. Common in written correspondence and formal speech.
Thank you for your letter the other day.
I am writing to reply to the contents of your esteemed letter.
お手紙 is a polite but less formal way to refer to someone's letter. 尊翰 is more literary and honorific, suitable for very formal correspondence.
Standard kanji spelling for this honorific term.
Alternate kanji spelling; less common than 尊翰.
Composed of 尊 (respect, honor) and 翰 (writing brush, letter). The exact historical derivation is uncertain, but the spelling is conventionally associated with respectful reference to another's letter.