The definition of formidable is something that causes fear and is difficult to overcome.(adjective)
An example of formidable is a boxer having a match with the current title holder.
See formidable in Webster's New World College Dictionary
Origin: ME < OFr < L formidabilis < formidare, to fear, dread < formido, fear < IE *mormo-, to feel horror > Gr mormoros, fear
See formidable in American Heritage Dictionary 4
Origin: Middle English
Origin: , from Old French
Origin: , from Latin formīdābilis
Origin: , from formīdāre, to fear
Origin: , from formīdō, fear.
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