Mister Tigan was the Trill husband of Yanas, and father of Janel, Ezri, and Norvo. By 2375, the couple had separated and he had left the Tigan home. (DS9: "Prodigal Daughter")
Within the first three months of joined with the Dax symbiont, Ezri's encounters with her mother and father left her feeling like: "My parents, my friends, my crewmates, it's like they don't even know me anymore." (DS9: "Shadows and Symbols")
The name of Ezri's father was mentioned in her personnel file in "Field of Fire" but was nearly undecipherable. It might be "Lazo".
In scenes cut from "Prodigal Daughter
", Ezri mentions her father stays away to avoid her mother, though he was planning to return for Norvo's trial