Pronunciation: (un"ri-len'ting),[key] —adj. 1. not relenting; not yielding or swerving in determination or resolution, as of or from opinions, convictions, ambitions, ideals, etc.; inflexible: an unrelenting opponent of the Equal Rights Amendment. 2. not easing or slackening in severity: an unrelenting rain. 3. maintaining speed, effort, vigor, intensity, rate of advance, etc.: an unrelenting attack.