formidable

 
Pronunciation: /ˈfɔːmɪdəb(ə)l, fɔːˈmɪd-/

adjective

  • inspiring fear or respect through being impressively large, powerful, intense, or capable: a formidable opponent

Derivatives

formidableness

noun

formidably

adverb

Origin:

late Middle English: from French, or from Latin formidabilis, from formidare 'to fear'

There are two possible pronunciations of formidable: one with the stress on the for- and the other with the stress on the -mid-. The second pronunciation is now common in British English, but the traditional pronunciation places the stress on the first syllable. Both pronunciations are acceptable in modern standard English.