(s)mightyhaving or showing great strength or force or intensity“struck a mighty blow”, “the mighty logger Paul Bunyan”, “the pen is mightier than the sword” (Bulwer-Lytton)
(r)mighty, mightily, powerful, right(Southern regional intensive) very; to a great degree“the baby is mighty cute”, “he's mighty tired”, “it is powerful humid”, “that boy is powerful big now”, “they have a right nice place”, “they rejoiced mightily”