1
: very powerful or strong : deserving serious attention and respect
a formidable enemy/opponent/weapon
2
: very difficult to deal with
The mountains were a formidable barrier.
a formidable challenge/task
3
: large or impressive in size or amount
He has mastered a formidable amount of material.
Cite this Entry
“Formidable.” Merriam-Webster.com Simple Definition, Merriam-Webster, https://www.merriam-webster.com/simple/formidable. Accessed 8 Jun. 2026.
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