Use the adjective much to mean a lot or a large amount. If you don't get much sleep the night before a big test, you don't get a lot. If you get too much sleep, you may sleep through your alarm and miss the test. Find 136 different ways to say MUCH, along with antonyms, related words, and example sentences at Thesaurus.com. 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. Much definition: Great in quantity, degree, or extent. MUCH meaning: 1. a large amount or to a large degree: 2. a far larger amount of something than you want or need…. Learn more. Define much. much synonyms, much pronunciation, much translation, English dictionary definition of much. adj. more , most Great in quantity, degree, or extent: not. Synonyms for MUCH: significant, important, major, big, historic, substantial, meaningful, eventful; Antonyms of MUCH: little, small, slight, trivial, minor. MUCH definition: great in quantity, measure, or degree. See examples of much used in a sentence. Much is now generally used with uncountable nouns. The equivalent used with countable nouns is many. In positive contexts, much is widely avoided: I have a lot of money instead of I have much money. There are some exceptions to this, however: I have much hope for the future. A lot of these cases are emotive transitive verbs and nouns. I have much need for a new assistant. In parallel, I need. The meaning of MUCH is great in quantity, amount, extent, or degree. How to use much in a sentence.