Benmohel, Nathan Lazarus (1802/3–69), linguist, was born in Hamburg, Germany, son of Lazarus Benmohel (d. 1841), a rabbi, and his wife, a rabbi's daughter. He settled in Ireland c.1827–9 as a teacher of languages in Dublin. Aged twenty-nine, he entered TCD (6 February 1832), where he won prizes in Hebrew and was awarded a BA (spring 1836) and an MA (1846), thus becoming the first Jew to graduate at an anglican university. He is said to have taught German, French, and perhaps Hebrew there (1839–42), after which his career is uncertain: no mention of him occurs in Thom's Irish Almanac until the late 1860s, when his title is given as ‘Professor’.
A versatile linguist, who knew Hindi and was influenced by the Grimms, he read a paper, ‘Etymological criticism’, to the Royal Irish Academy (RIA Proc., v (1850–53), 75–81) and wrote on etymology (though he did not always publish his work) until shortly before his death, which occurred at Sandycove, Co. Dublin, on 22 December 1869. Benmohel was reputed to be unorthodox and lax in his Judaism and cut himself off from his co-religionists, but he requested to be buried in the Jewish cemetery at Ballybough and so was buried on the periphery without full rites. He appears not to have married. A brother, Alexander Lazarus Benmohel (1788–1839), who came with him to Dublin, traded as a japanner and wholesale furrier (dealing in rabbit skins) in New Row West until his death; he was president of the Dublin Jewish congregation; Alexander's widow, Rosa or Rosanna (who remained close to Nathan), continued the business until the 1870s.