Dinin Do'Urden is one of Drizzt's two older brothers. Dinin is the son of Matron Malice and Rizzen, first appearing in R.A. Salvatore's Dark Elf Trilogy, beginning with Homeland which is the first Drizzt book chronologically. He also appears in the following two books in the series. He does not make an appearance in the Icewind Dale Trilogy, but however makes a return in first book of the Legacy of the Drow series, The Legacy.
In the opening chapters of Homeland, when House Do'Urden goes to war against House DeVir, Dinin unwittingly saves the life of infant Drizzt by murdering his older brother Nalfein, thus making Drizzt the Secondboy of House Do'Urden rather than the Thirdboy.
Dinin was also a master of Melee-Magthere until the beginning of the Do'Urden-Hun'ett conflict. When House Do'Urden was destroyed by House Baenre he was spared by Jarlaxle under the conditions that he join the mercenary band Bregan D'aerthe. He was a trusted ally of Jarlaxle until he was turned into a drider by his sister Vierna.
Dinin Do'Urden meets his end, while still in the form of a drider, as it so happens, during Vierna's raid on Mithril Hall, after being slain by Bruenor Battlehammer.