persistent

Adjective

• stubbornly unyielding
  • dogged persistence
    
  • dour determination
    
  • the most vocal and pertinacious of all the critics
    
  • a mind not gifted to discover truth but tenacious to hold it- T.S.Eliot
    
  • men tenacious of opinion
    

• retained; not shed
  • persistent leaves remain attached past maturity
    
  • the persistent gills of fishes
    

• continually recurring to the mind
  • haunting memories
    
  • the cathedral organ and the distant voices have a haunting beauty- Claudia Cassidy
    

• never-ceasing
  • the relentless beat of the drums
    

Related words

• Synonyms: 
  dogged , dour , pertinacious , tenacious , unyielding , lasting , haunting , relentless , unrelenting
• Antonyms: 
  caducous , shed