redoubtable Synonyms

unnerving formidable greatest notable mighty leading indomitable impressive important illustrious horrific horrid horrible potent powerful awe-inspiring influential tremendous tough terrific terrible tenacious strong steadfast stalwart respected horrendous high-stomached gutty dread dreaded dominant direful dire determined daunting commanding awful awesome appalling dreadful feared grim gruesome great glorious ghastly frightful frightening foremost