nonrelenting

• a word derived from relent.
  relent

  verb (used without object)

  to soften in feeling, temper, or determination; become more mild, compassionate, or forgiving.

Related Words

• acquiesce
• capitulate
• cave in
• come around
• comply
• ease off
• give in
• give up
• let go
• quit
• relax
• slacken
• soften
• subside