信しん約やくじ字FuriganaMeanings1nounvow; promise; pledgeA formal or solemn promise, often implying a strong sense of trust or faith. Slightly literary or formal in tone.彼かれは友ゆう人じんに信しん約やくを立たてた。He made a vow to his friend.信しん約やくを破やぶることは許ゆるされない。Breaking a pledge is unforgivable.