fitness

fitness — noun

1. the state of having a body that works well — you are strong, have energy, and ca

1.nounB1
Definition

the state of having a body that works well — you are strong, have energy, and can move and do physical activities without getting too tired.

Example

Trang goes to the gym every morning to improve her fitness.

collocation: improve + fitness

The personal trainer gave Ryo a fitness test to measure his stamina.

collocation: fitness test

Common collocations
  • improve fitness
  • build fitness
  • maintain fitness
  • fitness class
  • fitness test
  • fitness program
  • fitness level
  • good fitness
  • poor fitness
  • physical fitness
  • overall fitness
Synonyms
  • health

    broader term that includes mental and social wellbeing, not just physical condition

  • stamina

    focuses specifically on endurance over time, not overall physical condition

  • shape

    informal; used in phrases like 'in shape' or 'out of shape' to mean fitness level

  • strength

    only one component of fitness (muscular power); fitness also includes flexibility and stamina

Antonyms
  • weakness

    opposite end of the physical capability spectrum

  • unfitness

    direct opposite, but less common in everyday speech

Grammar Patterns

adjective + fitness (e.g. good fitness, poor fitness, overall fitness)

fitness + noun (e.g. fitness class, fitness test, fitness program)

verb + fitness (e.g. improve fitness, build fitness, maintain fitness)

Usage Note

Often used with verbs like 'improve', 'build', 'maintain', and 'regain', or with adjectives like 'good', 'poor', 'excellent', and 'overall'. Avoid using a plural form — fitness is uncountable.

Common Mistakes

She does exercises to keep her fitnesses up.
She does exercises to keep her fitness up.
Fitness is an uncountable noun and has no plural form.
I want to make my fitness better.
I want to improve my fitness.
'Improve fitness' is the standard collocation rather than 'make fitness better'.

2. the degree to which a person, thing, or idea meets the needs or requirements of

2.nounB2
Definition

the degree to which a person, thing, or idea meets the needs or requirements of a particular situation — for example, whether a candidate is right for a job, or a product is safe enough for a specific use.

Example

The company tests the fitness of new software before releasing it to customers.

fitness of + product/object

The manager questioned Nora's fitness for the role after she missed several deadlines.

fitness for + role

Common collocations
  • fitness for a role
  • fitness for purpose
  • fitness of a person
  • fitness of the equipment
  • fitness to drive
  • fitness to work
  • fitness to practise
  • question someone's fitness
  • assess fitness
  • review fitness
  • fitness for use
Synonyms
  • suitability

    more general and slightly more common than fitness in non-evaluative contexts

  • appropriateness

    emphasises correct fit for social or ethical standards rather than functional requirements

  • qualification

    often refers to formal credentials like degrees or certificates

  • readiness

    emphasises preparation and being ready, not just matching requirements

Antonyms
  • unsuitability

    direct opposite, common in formal writing about candidates or products

  • inappropriateness

    focuses on not matching social or contextual expectations

Grammar Patterns

fitness for + role/purpose (e.g. fitness for the job, fitness for use)

fitness of + person/thing (e.g. fitness of the candidate, fitness of the equipment)

fitness + to-infinitive (e.g. fitness to drive, fitness to work)

Usage Note

Common in formal or evaluative contexts such as hiring decisions, safety assessments, and legal qualifications. Frequently followed by 'for' (fitness for a role) or 'to' + infinitive (fitness to drive). Unlike the physical-health sense, this meaning often appears in phrases like 'fitness for purpose' or 'fitness to practise' in professional settings.

Common Mistakes

The doctor checked his fitnesses for the job.
The doctor checked his fitness for the job.
Fitness is uncountable even in this sense; do not add -es.
The board reviewed her fitness with the position.
The board reviewed her fitness for the position.
The correct preposition is 'for', not 'with'.

Word family

Synonym discussion

Sense: noun/1

While health is a broad term covering physical, mental, and social wellbeing, fitness focuses specifically on the body's ability to perform physical tasks. Stamina is a component of fitness related to endurance over time, whereas strength refers to muscular power. In informal conversation, speakers often use shape instead of fitness — for example, 'I am out of shape' means the same as 'my fitness is poor'. A regular jogger may have great stamina but not much upper-body strength, showing that fitness includes multiple abilities. For everyday use, fitness is the most neutral and widely understood term for overall physical readiness.

health ↗staminastrength ↗shape ↗

Common collocations

Nouns

Phrases

  • level of fitness
  • standard of fitness
  • state of fitness

Prepositions

Etymology

Old NorseMiddle EnglishModern English

Fitness comes from the adjective fit, meaning 'suitable or proper', combined with the suffix -ness, which turns adjectives into nouns. The word fit can be traced back through Middle English, possibly from Old Norse fitja (to knit or put together). The sense of 'physical health' developed in the 1800s, when people began using fit to describe a body that was well-prepared and capable — much like something that is 'fit for its purpose'.