from The American Heritage® Dictionary of the English Language, 4th Edition
- adj. Unyielding in severity or strictness; unrelenting: relentless persecution.
- adj. Steady and persistent; unremitting: the relentless beat of the drums.
from Wiktionary, Creative Commons Attribution/Share-Alike License
- adj. Unrelenting or unyielding in severity
- adj. Unremitting, steady and persistent
from the GNU version of the Collaborative International Dictionary of English
- adj. Unmoved by appeals for sympathy or forgiveness; insensible to the distresses of others; destitute of tenderness; unrelenting; unyielding; unpitying.
from The Century Dictionary and Cyclopedia
- Incapable of relenting; unmoved by pity; unpitying; insensible to the distress of others; destitute of tenderness.
- Synonyms Implacable, etc. See inexorable, and list under unrelenting.
from WordNet 3.0 Copyright 2006 by Princeton University. All rights reserved.
- adj. not to be placated or appeased or moved by entreaty
- adj. never-ceasing
relent + -less (Wiktionary)