inflexible

inflexible — adjective

1. used to describe a person, rule, or system that completely refuses to change or

1.adjectiveB2
Definition

used to describe a person, rule, or system that completely refuses to change or accept different ideas or ways of doing things.

Example

The school's dress code was inflexible — even a different colour of socks was not allowed.

inflexible + noun (dress code, rule, system)

Ayesha found her manager's inflexible attitude frustrating when she asked for a later start time.

be + inflexible + about [something]

Common collocations
  • inflexible rules
  • inflexible attitude
  • inflexible system
  • inflexible about
  • inflexible in
  • inflexible approach
Synonyms
  • rigid

    more neutral and technical; often used for systems and structures rather than people

  • uncompromising

    implies a refusal to make concessions, which can be positive (standing by principles) or negative

  • unyielding

    more formal; suggests firm resistance against pressure

  • stubborn

    more personal and mildly negative; focuses on the person's character rather than the rule

Antonyms

Grammar Patterns

be + inflexible + about/in [something]

Usage Note

Often used with the prepositions 'about' or 'in' — for example, 'inflexible about the deadline' or 'inflexible in their methods'. The subject is typically a person in authority, an organisation, or a set of rules.

Common Mistakes

She is inflexible to change the schedule.
She is inflexible about changing the schedule.
'inflexible' requires the preposition 'about' or 'in', not a to-infinitive.
My father is very inflexible.' (when describing a person's strict parenting style)
My father is very strict.
'strict' is more natural when the focus is on enforcing rules; 'inflexible' emphasises the refusal to adapt.

2. describes a material or object that is so stiff that it is difficult to bend, fo

2.adjectiveB2
Definition

describes a material or object that is so stiff that it is difficult to bend, fold, or change its shape.

Example

The metal bar was too inflexible to fit into the curved frame.

too inflexible to [do something]

Caio's art project needed a plastic sheet that was not too inflexible to curl.

Common collocations
  • inflexible material
  • inflexible sole
  • inflexible metal
  • inflexible plastic
  • inflexible bar
Synonyms
  • stiff

    the most common everyday word; can describe body parts, fabrics, and materials

  • rigid

    more technical; suggests a structure that holds its shape firmly under pressure

  • unyielding

    emphasises that the object does not give way when force is applied

Antonyms
  • flexible

    bends easily without breaking

  • supple

    bends and moves smoothly; often used for leather, fabric, or body movements

Grammar Patterns

be + inflexible

inflexible + noun

Usage Note

Primarily describes materials, tools, and natural objects. For a person's body, 'stiff' is the more natural everyday word — for example, 'My neck feels stiff' rather than 'inflexible'.

Common Mistakes

After sitting for hours, my back feels inflexible.
After sitting for hours, my back feels stiff.
'stiff' is the standard word for body parts that are hard to move.
The cardboard is inflexible so it cannot fold.
The cardboard is too stiff to fold.
'stiff' or 'rigid' are more common than 'inflexible' for describing everyday materials.

Word family

Synonym discussion

Sense: adjective/1

While all four describe resistance to change, they differ in scope and tone. 'Rigid' is more neutral and technical — it usually describes systems, structures, or rules that cannot adapt (e.g., 'a rigid hierarchy'). 'Stubborn' is personal and mildly negative, focusing on a person's character rather than a policy: a stubborn friend refuses to listen to reason. 'Uncompromising' can be either positive (standing by strong principles) or negative (refusing to negotiate at all), and is often used for negotiators, leaders, or moral stances. 'Unyielding' is more formal and suggests determination against pressure. For example, a manager might be 'inflexible about deadlines' (a neutral observation of policy) but 'stubborn about the seating chart' (a criticism of personality), while 'uncompromising safety standards' implies a principled choice.

rigid ↗stubborn ↗uncompromisingunyielding

Common collocations

Adverbs

  • completely inflexible
  • too inflexible
  • seemingly inflexible
  • often inflexible
  • rather inflexible

Etymology

LatinFrenchEnglish

From Latin 'inflexibilis', meaning 'not capable of being bent'. The word is formed from the prefix 'in-' ('not') and 'flexibilis' ('pliable, flexible'), which itself comes from the verb 'flectere' ('to bend'). English borrowed it from French 'inflexible' in the 1300s. The figurative sense — describing someone who refuses to change their mind — appeared in the 1500s, extending the original physical meaning.