noun
short letter; brief note
Rare, literary term for a short letter or note. Not used in everyday conversation; found in older or formal written contexts.
彼から寸簡が届いた。
I received a short letter from him.
noun
Humble, rare term used to refer to one's own letter. It is self-deprecating and would be used in very formal or old-fashioned correspondence.
先日は寸簡を差し上げました。
I sent you a brief letter the other day. (humble)
Composed of 寸 (a small unit of length, suggesting brevity) and 簡 (a letter or document). The exact historical derivation is uncertain, but the compound is a literary coinage for a short letter.