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Antonyms Starting With I
Inefficacious

Antonyms for inefficacious

1 antonym
16 synonyms

adjective

1

Antonyms

adj.: efficacious formal

Labelsformal formal or literary

2

Synonyms

ineffective, inefficient, futile

All synonyms for inefficacious →

Synonyms, antonyms and shades of meaning in English.

Synonyms from A to Z Antonyms from A to Z

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Sources. Senses, definitions and relations from Wiktionary (CC BY-SA 4.0) · Open English WordNet (CC BY 4.0) · Moby Thesaurus II, Roget’s Thesaurus (1911), Fernald (1914), Webster (1913) and other public-domain synonym dictionaries · ConceptNet (CC BY-SA 4.0) · spelling variants VarCon · example sentences Tatoeba (CC BY 2.0 FR) · word history Google Books Ngram (CC BY 3.0) · syllables CMU Pronouncing Dictionary (BSD) · frequencies wordfreq (CC BY-SA 4.0) and fastText vectors (CC BY-SA 3.0). Source details.

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