noun, noun or participle which takes 'suru', transitive verb
opening a letter; unsealing
Formal or literary term for opening a sealed letter or document. Rare in everyday speech; 開封 (かいふう) is the usual modern word.
古い手紙を開披すると、中から写真が出てきた。
When I opened the old letter, a photograph fell out.
開封 is the standard modern word for opening a sealed envelope or package. 開披 is a rare, formal synonym.
Compound of 開 (open) and 披 (spread, open). The exact historical derivation is uncertain; the spelling is conventionally associated with the meaning of opening a letter.