noun
letter of severance; Dear John letter
A formal written notice ending a personal relationship, often a romantic one. The term 絶縁状 is somewhat literary and dramatic; in modern casual contexts people might simply say 別れの手紙.
彼女から突然絶縁状が届いた。
I suddenly received a letter of severance from her.
絶縁状を書くのはとても辛かった。
Writing a Dear John letter was very painful.
別れの手紙 is a more common, everyday term for a breakup letter, whereas 絶縁状 sounds more formal and final.
Compound of 絶縁 (severance of ties) + 状 (letter, document). The exact historical derivation is uncertain, but the term follows a common pattern for formal written notices.