IPA: /rɪˈlɛntləsnəs/
KK: /rɪˈlɛntləsnəs/
The state of not giving up or stopping; continuing without becoming weaker or less intense.
Her relentlessness in pursuing her goals inspired everyone around her.
Relentlessness is formed from "relent" (from Old French *relentir*, meaning to soften or become less severe) and the suffix "-lessness" (meaning the state of being without). The word describes the state of being without relent, or the quality of being unyielding and persistent.
Think of the word 'relent' meaning to soften or ease up, and remember that 'relentlessness' means the state of not softening or giving in.