INFLEXIBLE

adj. unbending, stiff, rigid, firm, rigorous, unyielding, adamant, severe, Rhadamanthine, inelastic, hard (and fast), determined, fixed, obdurate, immovable, intractable, unvaried, unvarying, invariable, unchangeable, immutable, obstinate, stubborn, obstinate, pigheaded, mulish, dyed in the wool, headstrong, refractory, steely, stony, resolute, resolved, unadaptable, unaccommodating, uncompliant, uncompromising, unshakeable or unshakable The committee remain inflexible about changing the rules of the club to admit women