unfailing

Adjective

• unceasing
  • unfailing loyalty
    
  • unfailing good spirits
    
  • unflagging courtesy
    

• always able to supply more
  • an unfailing source of good stories
    
  • a subject of unfailing interest
    

• not liable to failure
  • a foolproof identification system
    
  • the unfailing sign of an amateur
    
  • an unfailing test
    

Related words

• Synonyms: 
  unflagging , foolproof