unrelenting: Meaning and Definition of

un•re•lent•ing

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.