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Classic usage
Reading level: hard
Estimated CEFR level: C1 — Advanced
Estimated from word frequency; not an official CEFR classification.
First attested in the 1530s; borrowed from Latin corrōborātus (“strengthened”), perfect passive participle of corrōborō (“to support, corroborate”) (see -ate (verb-forming suffix) and -ate (adjective-forming suffix)), from con- (“together”) + rōborō (“to strengthen”), from rōbur, rōboris (“strength”). Regular participial usage of the adjective up until Early Modern English, otherwise archaic.
confirm, sustain, substantiate, support, affirm
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tap / space
Classic usage
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