great

from The American Heritage® Dictionary of the English Language, 5th Edition.

• adjective Very large in size, extent, or intensity.
• adjective Of a larger size than other, similar forms.
• adjective Large in quantity or number: synonym: large.
• adjective Extensive in time or distance.
• adjective Remarkable or outstanding in magnitude, degree, or extent.
• adjective Of outstanding significance or importance.
• adjective Chief or principal.
• adjective Superior in quality or character; noble.
• adjective Powerful; influential.
• adjective Eminent; distinguished.
• adjective Very good; first-rate.
• adjective Very skillful.
• adjective Enthusiastic.
• adjective Being one generation removed from the relative specified. Often used in combination.
• adjective Archaic Pregnant.
• noun One that is great.
• noun A division of most pipe organs, usually containing the most powerful ranks of pipes.
• noun A similar division of other organs.
• adverb Very well.
• adverb Used as an intensive with certain adjectives.

from The Century Dictionary.

• Unusually or comparatively large in size or extent; of large dimensions; of wide extent or expanse; large; big: as, a great rock, house, farm, lake, distance, view, etc.
• Large in number; numerous: as, a great multitude; a great collection.
• Exceeding or unusual in degree: as, great fear, love, strength, wealth, power.
• Widely extended in time; of long duration; long-continued; long: as, a great delay.
• Of large extent or scope; stately; imposing; magnificent: as, a great entertainment.
• Of large consequence; important; momentous; weighty; impressive.
• Chief; principal; largest or most important: as, the great seal of England; the great toe.
• Holding an eminent or a superlative position in respect to rank, office, power, or mental or moral endowments or acquirements; eminent; distinguished; renowned: as, the great Creator; a great genius, hero, or philosopher; a great impostor; Peter the Great.
• Grand; magnanimous; munificent; noble; aspiring: as, a great soul.
• Expressive of haughtiness or pride; arrogant; big: as, great looks; great words.
• Filled; teeming; pregnant; gravid.
• Hard; difficult.
• . Widely known; notorious.
• Much in action; active; persistent; earnest; zealous: as, a great friend to the poor; a great foe to monopoly.
• Much in use; much used; much affected;
• In geneal., one degree more remote in ascent or descent: generally joined with its noun by a hyphen, and used alone only for brothers and sisters of lineal ancestors, in other cases before the prefix grand-: as, great-uncle, great-aunt (brother or sister of a grandparent); great-grandfather, great-grandson, great-grandneph-ew.
• In music, in the comparative, same as major: as, greater third (a major third), etc.
• In a wider sense, a colon or series.
• The forty years' division, a. d. 1378-1417, between different parties in the Latin or Roman Catholic Church, which adhered to different popes.
• The Black Sea.
• The corresponding season of the church year, from Easter to Ascension.
• noun 1. The whole; the gross; the mass; wholesale: as, to work by the great.
• noun . A great part; the greater part; the sum and substance.
• noun plural The great go at Cambridge. See go, n., 3.
• To become great or large; grow large; enlarge.
• To become great with child; become pregnant.