adjective
1.
Synonyms: stiff 1, immalleable, impliable, incompliant, inelastic, rigid, unbending, unflexible, unyielding
Related Word: immobile, immovable
Contrasted words: elastic, resilient, springy, supple; ductile, malleable, plastic, pliable, pliant; fluid, liquid
Antonyms: flexible
2.
rigidly firm in will or purpose
a person of inflexible resolution
Synonyms: adamant, adamantine, brassbound, dogged, inexorable, iron, obdurate, relentless, rigid, rockbound, rock-ribbed, single-minded, steadfast, stubborn, unbendable, unbending, uncompliant, uncompromising, unswayable, unyielding; compare stiff 1
Related Word: intractable, obstinate; indomitable, invincible, unconquerable; grim, hard, implacable, unrelenting; dyed-in-the-wool, fixed, set, ||sot
Contrasted words: agreeable, amenable, compliant, docile, pliant, responsive, swayable, yielding; mild, open
Antonyms: flexible
3.
incapable of changing or being changed
inflexible rules
Synonyms: constant, determinate, fixed, immovable, immutable, inalterable, invariable, ironclad, unalterable, unchangeable, unmodifiable, unmovable
Related Word: strict; rigorous; established, set, settled; changeless, unchanging
Contrasted words: adaptable, adjustable, alterable, changeable, mutable, variable
Antonyms: flexible
4.
Synonyms: tough 3, hard-line, uncompromising, unyielding