Why does the Torah say “a month of days” with the word yerach rather than the usual word for month in the law of the captive woman?

This source-based Hagut Yosef essay explores the question: Why does the Torah say “a month of days” with the word yerach rather than the usual word for month in the law of the captive woman? The canonical Hebrew article develops the theme through Torah sources and reflection on human life. This localized discovery layer preserves the source’s meaning and identity and does not add new halakhic, historical, psychological, medical, legal, political, scientific, or empirical claims beyond the Hebrew source.