relentless
B2Adjective/US /rɪlˈɛntlɪs/ rĭl-ĔNTL-ĭs; UK /rɪlˈɛntlɪs/ rĭl-ĔNTL-ĭs/
Unmoved by appeals for sympathy or forgiveness; insensible to the distresses of others; destitute of tenderness; unrelenting; unyielding; unpitying; as, a prey to relentless despotism.
