To pass into use; to take or have effect; to be applied; to serve to the use or benefit of; as, a gift of lands inures to the heirs
To apply in use; to train; to discipline; to use or accustom till use gives little or no pain or inconvenience; to harden; to habituate; to practice habitually
To take effect, or to benefit someone. In property law, the term means "to vest". For example, Jim buys a beach house that includes the right to travel across the neighbors property to get to the water. That right of way is said, cryptically, "to inure to the benefit of Jim"