Source : Webster's Revised Unabridged Dictionary (1913)

Usufruct \U"su*fruct\ (?; 277), n. [L. usufructus, ususfructus,
   usus et fructus; usus use + fructus fruit.] (Law)
   The right of using and enjoying the profits of an estate or
   other thing belonging to another, without impairing the
   substance. --Burrill.

Source : WordNet®

usufruct
     n : a legal right to use and derive profit from property
         belonging to someone else provided that the property
         itself is not injured in any way