Immured means "confined," "shut in," "imprisoned," or "enclosed": "The flower beds were immured between gravel walks." "A country boy, he felt immured in his small room in the city." Inured (which may also be spelled enured) means "accustomed," "habituated," "hardened by exercise or custom": "His rugged early life inured him to labor and pain." "Recruits quickly become inured to the rigors of army life." "In later life, the benefits of social security inured to him and his family." See also inure.
Dictionary of problem words and expressions. Harry Shaw. 1975.