Naghm (pi. Anghām) and Naghmah (pi. Naghamāt) mean “Vocal melody”, both being derived from the Arabic “To speak, hum, or sing in a low pleasant tone”. Such were the classical meanings of those terms, in distinction from LAḤN (pi. ALḤĀN), which stood for “melody” whether in the vocal or instrumental art. Thus, one of the earliest Arabic books on music—the Kitāb al-naghm (Book of vocal melody)—by Yūnus al-Kātib (d. c. 765), became the source book on this subject. Then came Isḥāq al-Mauṣilī (d. 791) who wrote the Kitāb al-naghm wa'l-īqā' (Book of melody and rhythm). Yet the famous Kitāb al-aghānī of Al-Iṣfahānī (d. 967) introduces each song under the title of saut, although that is only done so as to indicate the singing (taghannī) of a poem. Later, the term naghm came to be used in a modal sense, equating with the Sanscrit rāga and jātī, and the Persian āvāz. We know of the naghm in the modal sense as early as Al-Kindī (d. c. 874), one of them (called ṭarā'iq) being known as Iṣfahān. In the Mafātiḥ al-'ulūm of Abū 'Abdallāh al-Khwārizmī (d. c. 1000), these modes (dasātīn) were attributed to the famous Bārbad of the court of Khusrau Parviz the Sāsānī ruler. Al-Mas'ūdī (d. c. 957) names one of these modes as mihrbānī (cf. mihrgānī) among the ancient Persian modes, whilst Ibn Zaila (d. 1048) mentions a mode (ḍarb) called nāqūsi, which is the 26th of the Sī laḥn of Khusrau va Shīrīn of Nīzāmī of Ganja (1203).