Indefatigable
hardPositive tonein-dih-FAT-ih-guh-bul
adjective
Definition
Persisting tirelessly; unable to be fatigued
Memory hook
IN-DE-FATIGABLE: NOT able to be FATIGUED — tirelessly persistent, never giving up.
Word roots
Learning roots unlocks whole word families. Study common GRE root words.
Examples
“The indefatigable researcher worked eighteen-hour days.”
“Her indefatigable efforts eventually led to success.”
Test yourself
Fill in the blank with the right word:
“The ______ researcher worked eighteen-hour days.”
Show answer
indefatigable
Categories
GRE Tip
Indefatigable is a hard-difficulty GRE word. On the GRE, you might see it paired with synonyms like "tireless" or "unwearying" in Sentence Equivalence questions. Look for contrast clues (however, despite, although) that signal the opposite meaning. Words like "lethargic".
Related GRE Words
tireless
Having or showing great effort or energy; indefatigable
devitalize
To deprive of strength, vitality, or energy
enervate
To cause someone to feel drained of energy; to weaken
impetus
The force or energy with which a body moves; a driving force
languorous
Characterized by tiredness or inactivity; pleasantly lazy
pertinacious
Holding firmly to an opinion or course of action; persistent
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