(died c. 990). Also called ben Librat, al-Abrad, and Adonim HaLevi - a translation of his Berber name as though it were Spanish dueños. Jewish Hebrew poet and linguist. He was probably born in Fez (in modern Morocco), a scion to a noble family, and studied in Baghdad under Rav Saadiah Gaon. He lived for a time in Córdoba. The year of his birth is unknown, but he seems to have lived to be over 60.

When in Córdoba, he became a sharp critic and opponent of Menahem ibn Saruk, Hisdai ibn Shaprut's secretary, who wrote a Hebrew dictionary, known as the Mahberet (the Notebook). Dunash wrote responsa against that dictionary, and presented them to ibn Shaprut (probably after 958). He claims to have disputed 200 items, but the extant text contains only 160 entries. Sixty eight are included in the poem LeDoresh haHokhmot (To the Man Who Requires Wisdoms), which is explained in parallel prose paragraphs, a literary form borrowed from technical Arabic literature. Many of Dunash' comments deal with those explanations which are likely to lead to error in matters of Halacha and belief. This religious factor may explain the severity of the attack. Though ibn Saruk was relieved of his position due to accusations of heresy, there is no evidence that Dunash deliberately caused his fall, or benefited from it in any way. Three of ibn Saruk's students (including Judah ben David Hayuj), came out against Dunash, writing responsa dealing with 50 items, which immitated Dunash' poem in form. Dunash' student, Yehudi ben Sheshet, answered sharply in the same manner. Rashi, who knew of the argument between the two schools, quotes Dunash about 20 times. Rabbi Jacob Tam wrote "decisions" on the disagreements between Dunash and ibn Saruk, and Rabbi Joseph Kimhi in his Sefer HaGalui (the Book of That Which Is Revealed) wrote against these decisions in favour of Dunash. Although Dunash is correct in most of his points, his grammatical method is no more advanced than that of his adversary, both being students of classical method.

The book Teshuvot al Rav Sa'adyah Ga'on (Responsa on Rav Saadiah Gaon) is also attributed to Dunash, but that attribution is often contested, as it is full of Arabisms, and, moreover, shows the influences of the new method in Hebrew Grammer. Some believe that the book was written in Dunash' old age, after the publication of Judah ben David Hayuj's books on grammer, where he founded the new method in Hebrew Grammer.

Dunash changed the course of Hebrew poetry by introducing quantitative metres and secular genres, verse-forms and images borrowed from the Arabic and was also the first to employ the new metrical technique in sacred poetry, thus laying the foundation for Hebrew medieval poetry. Though there was some opposition to these innovations, they were immediately accepted even by ibn Saruk's students. Solomon ibn Gabirol, in a paean to Judah HaLevi speaks of Dunash as the greatest poet of all time. Only a few of his poems have so far been discovered and most are known only by the lines quoted in the responsa. His religious poems include the piyutim Deror Yikra (Will Set Free) and Devai Hasser (Remove Pains), which has become part of the Grace said after the wedding meal. As was common at the time, his secular poems are songs of praise and friendship. They have strong moralistic overtones.