usefulness    akamaro
(person or object completely at end of ~) akāheze
En-En dictionary 
akāheze     7  class 7
singular: aka-,aga-
  
person or thing completely at end of usefulness (from guhera)
akamaro (utu-)     7  class 7
singular: aka-,aga-
plural: utu-,udu-
  
1. profit, benefit, usefulness, value, 2. objective, goal, 3. use, usage