untiring

IPA/ʌnˈtaɪərɪŋ/
IPA/ʌnˈtaɪərɪŋ/

untiring — adjective

  • untiringpositive
  • more untiringcomparative
  • most untiringsuperlative

1. always able to continue working hard or doing something with the same energy and

1.adjectiveC1
Definition

always able to continue working hard or doing something with the same energy and interest, without ever becoming tired or losing enthusiasm

Example

Dr. Andrei's untiring commitment to public health saved thousands of lives in rural villages.

collocation: untiring commitment to [something]

The volunteers showed untiring energy, working through the night to help flood victims.

collocation: untiring energy + participial phrase

Common collocations
  • untiring efforts
  • untiring energy
  • untiring enthusiasm
  • untiring dedication
  • untiring support
  • untiring work
  • untiring commitment
  • untiring in one's efforts
Synonyms
  • tireless

    most common synonym; similar in meaning and register, equally natural in most contexts

  • indefatigable

    more formal and literary; suggests a person who seems incapable of exhaustion

  • unflagging

    focuses on energy or enthusiasm that remains steady and never diminishes

  • persevering

    emphasizes continuing despite difficulties rather than physical energy

Antonyms
  • lazy

    suggests unwillingness to make an effort, opposite of active sustained work

  • lethargic

    suggests lack of energy or enthusiasm, opposite of energetic pursuit

Grammar Patterns

untiring + noun (efforts, energy, dedication)

untiring in + noun/noun phrase

Usage Note

Typically placed before nouns that describe effort, attitude, or personal qualities -- such as efforts, energy, enthusiasm, dedication, support, or commitment. Particularly common in formal writing and speech praising sustained achievement or service. The pattern 'untiring in [area]' can be used predicatively: 'She was untiring in her efforts to improve the school.'

Common Mistakes

She untiring to help others.
She is untiring in her efforts to help others.
untiring is an adjective, not a verb; it needs a form of 'be' and cannot be followed directly by 'to + verb'.

Word family

Synonym discussion

Sense: adjective/1

Tireless, indefatigable, unflagging, and persevering all describe sustained effort, but they differ in emphasis and register. Tireless is the most common and neutral synonym, suitable for both physical and mental work — for instance, describing a tireless campaigner or a tireless researcher. Indefatigable is more formal and often literary, calling attention to a person who seems incapable of exhaustion. Unflagging focuses specifically on the steady, never-diminishing quality of energy or enthusiasm, commonly used with nouns like support, interest, or optimism. Persevering emphasizes continuing despite obstacles rather than physical energy itself, so it describes a person's character more than the quality of their effort. A persevering student keeps trying after failing a test, whereas untiring effort would describe the relentless energy they bring to studying.

tireless ↗indefatigable ↗unflagging ↗persevering ↗

Common collocations

Nouns

Adverbs

Phrases

  • untiring in one's efforts to
  • with untiring energy

Prepositions

Etymology

Old EnglishEnglish

Formed in English by adding the prefix 'un-' (meaning 'not') to the adjective 'tiring', which comes from the verb 'tire' (from Old English tēorian, meaning 'to become exhausted or weary'). The word first appeared in the late 16th century and has remained in formal use to describe people or efforts that do not weaken.