Definition of formidable
- a formidable prospect
- a formidable opponent
- a formidable accomplishment
The mountains were a formidable barrier.
He has mastered a formidable amount of material.
These example sentences are selected automatically from various online news sources to reflect current usage of the word 'formidable.' Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. Send us feedback.
First Known Use: 15th century
in the meaning defined at sense 1
See Words from the same yeararduous, Augean, backbreaking, challenging, demanding, difficult, effortful, exacting, grueling (or gruelling), hard, heavy, herculean, killer, laborious, moiling, murderous, rigorous, rough, rugged, severe, stiff, strenuous, sweaty, tall, testing, toilsome, tough, uphill;
cheap, easy, effortless, facile, light, mindless, simple, soft, undemanding;
achievable, clear, doable, elementary, manageable, uncomplicated;
abstract, abstruse, complex, complicated, elusive, hairy, insoluble, intricate, involved, knotty, opaque, problematic (also problematical), recondite, serious, spiny, stubborn, thorny, ticklish, tricky;
bruising, burdensome, exhausting, labored, onerous, oppressive, stressful, taxing, tight, trying;
annoying, bothersome, distressing, irksome, troublesome, vexatious;
: very powerful or strong : deserving serious attention and respect
: very difficult to deal with
: large or impressive in size or amount
Thesaurus: All synonyms and antonyms for formidable Spanish Central: Translation of formidable Nglish: Translation of formidable for Spanish speakers Britannica English: Translation of formidable for Arabic speakers
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