King James Dictionary 
Mi'Ghty, a. Having great bodily strength or physical power very strong or vigorous as a mighty arm.
1. Very strong valiant bold as a mighty man of valor. Judges 6 . 2. Very powerful having great command.
3. Very strong in numbers as a mighty nation. Genesis 18 4. Very strong or great in corporeal power very able.
Wo to them that are mighty to drink wine. Isaiah 5
5. Violent very loud as mighty thunderings. Exodus 9; Psalms 68 6. Vehement rushing with violence as a mighty wind or tempest. Exodus 10; Revelation 6 7. Very great vast as mighty waters. Nehemiah 9 8. Very great or strong as mighty power. 2 Chronicles 26 9. Very forcible efficacious as, great is truth and mighty. 10. Very great or eminent in intellect or acquirements as the mighty Scaliger and Selden. 11. Great wonderful performed with great power as mighty works. Matthew 11 12. Very severe and distressing as a mighty famine. Luke 15 13. Very great, large or populous as a mighty city. Revelation 18 14. Important momentous.
I'll sing of heroes and of kings,
In mighty numbers mighty things.
Mi'Ghty, adv. In a great degree very as might wise mighty thoughtful. Colloquial.
Webster's Dictionary 
(1): ( n.) Accomplished by might; hence, extraordinary; wonderful.
(2): ( adv.) In a great degree; very.
(3): ( n.) A warrior of great force and courage.
(4): ( n.) Possessing might; having great power or authority.
(5): ( n.) Denoting and extraordinary degree or quality in respect of size, character, importance, consequences, etc.