official letter; personal message (from a high official)
Refers to a formal letter or message sent by a high-ranking official such as the Emperor, Prime Minister, or a head of state. Often used in diplomatic or governmental contexts.
The Prime Minister sent an official letter to the President.
The Emperor's personal message was handed to the ambassador.
handwritten letter; autograph letter
Emphasizes that the letter is written by hand, often by the sender personally. Can be used for personal correspondence, but still carries a somewhat formal tone.
He sent me a handwritten letter in his own hand.
The ambassador handed the president a personal letter from his head of state.
The prime minister entrusted the special envoy with a personal letter to deliver.
The king sent a personal letter to the leader of the neighboring country.
The foreign minister received personal letters from various countries.
書状 is an old-fashioned formal word for a written letter or document, while 親書 adds the specific nuance of personal or official authorship by a dignitary.
新書 (also read しんしょ) refers to a compact paperback book format, a completely different word from 親書, which means an official or personally written letter.
expert; connoisseur; person in the know · counter for messages and documents · worldly understanding; tact; insight · supernatural powers; magical powers
Composed of 親 (しん, 'parent; intimate; personally') and 書 (しょ, 'writing; document'). The combination suggests a document written personally or by someone in a close, authoritative relationship.