Synonyms of inflexible

inflexible

adjective

(ˌ)in-ˈflek-sə-bəl 

1

as in unchangeable

not capable of changing or being changed

the inflexible law of gravity

Synonyms & Similar Words

• unchangeable
• unchanging
• fixed
• invariable
• unalterable
• immutable
• steadfast
• hard-and-fast
• determinate
• inalterable
• constant
• established
• steady
• stable
• changeless
• unvarying
• incommutable
• immovable
• unaltered
• unmovable
• settled
• set

Antonyms & Near Antonyms

• flexible
• variable
• elastic
• changeable
• adaptable
• adjustable
• uncertain
• unstable
• mutable
• alterable
• fickle
• varying
• unsettled
• plastic
• pliable
• inconstant
• fluctuating
• pliant
• supple
• willowy

2

as in rigid

incapable of or highly resistant to bending

shoes made of inflexible plastic hurt my feet

Synonyms & Similar Words

• rigid
• stiff
• stiffened
• brittle
• solid
• unyielding
• strong
• hard
• dense
• compact
• sound
• inelastic
• crisp
• substantial
• firm
• arthritic
• rheumatic
• nonelastic
• nonmalleable

Antonyms & Near Antonyms

• flexible
• pliable
• floppy
• elastic
• pliant
• workable
• resilient
• supple
• yielding
• malleable
• stretchy
• plastic
• springy
• soft
• flabby
• flaccid
• semiflexible
• mushy
• squishy
• droopy
• squashy
• limp
• willowy
• limber
• lithe
• lank
• lissome
• lithesome
• lissom
• semisoft

3

as in strict

not allowing for any exceptions or loosening of standards

inflexible entry rules for the contest ban anyone who works for the company as well as any of their relatives

Synonyms & Similar Words

• strict
• rigorous
• rigid
• stringent
• uncompromising
• exacting
• steadfast
• hard-line
• adamant
• conscientious
• cast-iron
• meticulous
• stubborn
• unbending
• relentless
• punctilious
• undeviating
• scrupulous
• tenacious
• brassbound
• tough
• exact
• painstaking
• unflinching
• implacable
• unyielding
• fussy
• adamantine
• immovable
• close
• harsh
• determined
• resolved
• unrelenting
• dogged
• severe
• single-minded
• stern
• hardened
• firm
• austere
• demanding
• unsparing
• hard
• grim
• unappeasable
• flinty
• hard-hearted
• ironbound

Antonyms & Near Antonyms

• flexible
• loose
• lax
• slack
• relaxed
• compliant
• pliable
• easy
• pliant
• acquiescent
• soft
• lenient
• gentle
• mild
• yielding
• tolerant
• merciful
• indulgent
• easygoing
• kindly
• negligent
• compromising
• sloppy
• slovenly
• neglectful
• slipshod
• relenting
• remiss
• spoiling
• pampering
• unfussy

4

as in stubborn

sticking to an opinion, purpose, or course of action in spite of reason, arguments, or persuasion

her inflexible father was unmoved by tears and pleading, and he grounded her anyway

Synonyms & Similar Words

• stubborn
• adamant
• steadfast
• hardened
• unbending
• intransigent
• obstinate
• uncompromising
• implacable
• unyielding
• obdurate
• immovable
• wilful
• obsessive
• hard
• ossified
• unrelenting
• opinionated
• bullheaded
• mulish
• willful
• strict
• adamantine
• headstrong
• hardheaded
• pertinacious
• perverse
• persistent
• pigheaded
• dogged
• rigid
• pat
• determined
• hard-nosed
• stiff-necked
• self-willed
• relentless
• inconvincible
• self-opinionated
• iron
• deaf to reason
• stern
• inexorable
• tenacious
• wrongheaded
• severe
• unflinching
• hidebound
• resolved
• defiant
• uncooperative
• wayward
• hard-line
• cantankerous
• unmanageable
• narrow-minded
• intractable
• firm
• contrary
• single-minded
• recalcitrant
• disobedient
• stouthearted
• hard-shell
• anal-retentive
• refractory
• unruly
• contumacious
• insubordinate
• mutinous
• ungovernable
• indomitable
• invincible
• unconquerable
• demanding
• bloody-minded
• hard-shelled
• exacting
• set
• insurgent
• hell-bent
• inveterate
• cussed
• froward
• confirmed
• unregenerate

Antonyms & Near Antonyms

• flexible
• compliant
• amenable
• pliable
• agreeable
• pliant
• complying
• acquiescent
• obedient
• docile
• submissive
• yielding
• tractable
• responsive
• receptive
• willing
• accepting
• reasonable
• manageable
• placable
• relenting
• temperate
• slavish
• subservient
• persuadable
• governable

Synonym Chooser

How is the word inflexible distinct from other similar adjectives?

The words rigid and stiff are common synonyms of inflexible. While all three words mean "difficult to bend," inflexible stresses lack of suppleness or pliability.

ski boots with inflexible soles

In what contexts can rigid take the place of inflexible?

The words rigid and inflexible are synonyms, but do differ in nuance. Specifically, rigid applies to something so stiff that it cannot be bent without breaking.

a rigid surfboard

When might stiff be a better fit than inflexible?

The meanings of stiff and inflexible largely overlap; however, stiff may apply to any degree of this condition.

stretching keeps your muscles from becoming stiff

Example Sentences

Recent Examples of inflexible

Many adults continue to be excluded from tertiary education due to barriers such as location, cost, or inflexible schedules. —Wyles Daniel, USA Today, 26 July 2025

Yet our justice system treats them all the same, with inflexible, punitive responses that disproportionately harm Black youth, as former Secretary of Juvenile Services Vincent Schiraldi noted upon his resignation. —Olivia Naugle, Baltimore Sun, 19 July 2025

Plans allege providers drive up costs with unnecessary procedures, tests and prescription medications; providers say plans are inflexible and stand in the way of appropriate patient care. —Sachin H. Jain, Forbes.com, 23 June 2025

Ricky Flanagan Orlando Trump assigns guilt without due process President Donald Trump’s inflexible position in the deportation of a Maryland man, Kilmar Abrego Garcia, is reminiscent of Trump’s fervor in the 1989 case of the Central Park Five. —Letters To The Editor, The Orlando Sentinel, 4 May 2025