Adjective: relentless ri'lent-lus
- Never-ceasing
"the relentless beat of the drums";
- persistent, unrelenting
- Not to be placated, appeased or moved by entreaty
"relentless persecution";
- grim, inexorable, stern, unappeasable, unforgiving, unrelenting
See also: continual, implacable
Encyclopedia: Relentless