noun
Refers to integrity, good faith, or faithfulness to another person or promise. As a standalone noun, 信 is formal and often appears in set or elevated phrasing.
商売では信が第一だ。
In business, integrity comes first.
彼は友との信を最後まで守った。
He remained faithful to his friend to the end.
noun
Used for the trust or confidence placed in a person, government, statement, judgment, and similar things. Common collocations include 信を置く, 信を得る, and 信を失う.
政府は国民の信を失った。
The government lost the people's trust.
私は彼の判断に信を置いている。
I have confidence in his judgment.
noun
religious faith; devotion
Religious use meaning faith or devotion toward a deity, Buddha, doctrine, or religious path. In everyday modern Japanese, 信仰 or 信心 is often more explicit.
修行を通じて、彼は仏への信を深めた。
Through religious practice, he deepened his faith in the Buddha.
counter
counter for received messages
Rare counter use for received messages such as telegrams or correspondence. It is much less ordinary than counters such as 通 in modern Japanese.
古い記録には「電報一信を受け取る」のような数え方が見られる。
In old records, you may see counting such as 'receive one telegram.'