Abu'l-Ḥasan Aḥmad ibn Jaʿfar al-Barmakī al-Nadīm (839 – June/July 936), surnamed Jaḥẓa (Arabic: جحظة, lit.
'the lute player'), was a descendant of the Barmakid family, and a well-known scholar, singer, poet, and courtier of his time.
He was reportedly born in 839, the grandson of Musa ibn Yahya and great-grandson of the famous Yahya al-Barmaki, the vizier of Harun al-Rashid.
[1] The historian Charles Pellat describes him as "a man of very varied culture, but little religion, of doubtful morals and repulsive appearance"; he was nicknamed Jaḥẓa by the Abbasid prince and poet Ibn al-Mu'tazz, on account of his bulging eyeballs.
[1] Little of his work survives, apart from a few poems; most of them are known through a list in the 10th-century compendium al-Fihrist, and include treatises on astrology, lute-playing, cooking, and a biography of Caliph al-Mu'tamid.