unvarying

Adjective

• always the same; showing a single form or character in all occurrences
  • a street of uniform tall white buildings
    

• lacking variety

• unvarying in nature
  • maintained a constant temperature
    
  • principles of unvarying validity
    

Related words

• Synonyms: 
  uniform , unvaried , changeless , constant , invariant
• Antonyms: 
  multiform , varied