indefatigable - Master This Word
Master this word with our 5-step learning method – Learn English in English
indefatigable Word Meanings
- unable to be tired out
- persistently relentless
- showing sustained enthusiasm
indefatigable Example Sentences
Example sentences are the start of understanding. Don't rush to memorize. First feel how the word works in a sentence.
indefatigable Phonetic & Pronunciation
UK
/ˌɪndɪˈfætɪɡəbl/
US
/ˌɪndɪˈfætɪɡəbl/
indefatigable Word Etymology
in- = not, defatigable = able to be tired. Origin: Latin → Old French → English. Imagine a person running a marathon without showing any sign of fatigue, as if powered by indomitable energy.
Note 1: These definitions and etymologies are not standard dictionary definitions, but extended explanations provided to help with memorization and understanding of the actual application of words. Through this background information, we strive to make words more vivid and easier to understand, and help you remember their meanings in real life.
Note 2: LexiTalk designs the learning flow around the linguistics principle of “Comprehensible Input.” When learners encounter material that is slightly above their level but still understandable from context, the brain naturally absorbs the language. That’s why we keep every word inside authentic contexts, using examples and associations to help you understand it and use it flexibly.
Read the FAQ explanation of Comprehensible InputReal Context
Indefatigable describes a person or spirit that cannot be tired or worn out, even after long, demanding efforts. It emphasizes sustained energy, persistence, and enthusiasm over time, not just a momentary burst of grit. In usage, it often praises athletes, activists, or workers who keep going through setbacks, long projects, or harsh conditions. The tone is admiring and almost heroic, suggesting resilience and optimism rather than stoic detachment. While closely related to tireless or untiring, indefatigable foregrounds ongoing stamina and a positive outlook. The noun form is indefatigability, and the adjective can pair with people, teams, or movements that endure over extended periods.
Usage Reminders
- - It describes a person or spirit that does not get tired easily.
- - It emphasizes sustained energy and persistence, not just a momentary burst of grit.
- - It is positive and often used to praise endurance in work, sport, or activism.
- - It is not the same as ignoring fatigue or burnout; context matters.
- - Use with people or personas who show long-term stamina and optimism.
Common Misconceptions
- It means never gets tired under any circumstances.
- It means you are stubborn and refuse to listen to fatigue.
- It implies ignoring fatigue or burnout.
- It is only used for heroic, extraordinary people.
- It can describe a machine or process as tireless.
Thinking Differences
English typically frames indefatigable as a heroic, almost aesthetic stamina; learners may over-generalize it as 'never tired' and overuse it in casual talk rather than in focused, long-term contexts.
Learning Tips
- Practice with contrasting pairs (indefatigable vs tireless).
- Note contexts: sports, activism, long projects.
- Replace with synonyms to feel nuance (untiring, untiring).
- Create mini-scenarios to test tone: admiration vs. stubbornness.
- Read sample sentences aloud to feel rhythm.
- Use the noun indefatigability in formal writing.
5-Step Learning Method - Learn English in English
Step 2: Usage
Which of the following sentences uses 'indefatigable' correctly?
A.The cat showed indefatigable curiosity towards the new toy.
B.She took an indefatigable nap in the afternoon.
C.He was known for his indefatigable work ethic.
D.They went on an indefatigable vacation.
Step 3: Similar Words
Select the synonym for 'indefatigable':
A.Lethargic
B.Persistent
C.Sluggish
D.Idle
Step 4: Opposite Words
Select the word that is the opposite of 'indefatigable':
A.Energetic
B.Lazy
C.Vigorous
D.Diligent
Step 5: Mastery
How would you describe someone who is indefatigable in a work environment?
A.Procrastinator
B.Hardworking
C.Forgetful
D.Disorganized
Want to practice more words?
Download LexiTalk app for personalized learning experience
Download App