uncompromising

adj

1. rigid, stiff, hard, inflexible, unflexible, nonflexible, unbendable, unbending, unyielding, hard-line; fixed, set, firm, immovable, unalterable, unchangeable, unvarying, hard-and-fast, ironclad, absolute, resolved, determined, tenacious, dogged, persevering, unrelenting, relentless, implacable, inexorable, never-say-die, die-hard; hardcore, inveterate, absolute, unqualified, unmitigated.

2. strict, severe, stern, austere, Spartan, harsh, Inf. hard as nails, tough; rigid, Inf. set in one's ways, narrow-minded, close-minded; ultraconservative, strait-laced, Sl. straight, on the straight and narrow; unadaptable, unaccommodating, unconformable, nonconforming, noncompliant, uncompliant, non-cooperative, uncooperative; stubborn, obstinate, pigheaded, mulish, obdurate, headstrong, willful.