Much definition: Great in quantity, degree, or extent. (in combinations such as ' as much ', ' this much ') Used to indicate, demonstrate or compare the quantity of something. MUCH definition: 1. a large amount or to a large degree: 2. a far larger amount of something than you want or need…. Learn more. Synonyms for MUCH: significant, important, major, big, historic, substantial, meaningful, eventful; Antonyms of MUCH: little, small, slight, trivial, minor, insignificant, unimportant, negligible Easy Learning Spanish Grammar. We use the quantifiers much, many, a lot of, lots of to talk about quantities, amounts and degree. We can use them with a noun (as a determiner) or without a noun (as a pronoun). … MUCH definition: great in quantity, measure, or degree. See examples of much used in a sentence. The meaning of MUCH is great in quantity, amount, extent, or degree. How to use much in a sentence. Much is used as an adjective or adverb, but it always means a large quantity, extent, or degree. When something hurts very much, it's very painful, and when your friend says your gift is very much appreciated, she's emphasizing how happy it made her. 1. A large quantity or amount: Much has been written. 2. Something great or remarkable: The campus wasn't much to look at.