Main/meɪn/ Definition 1 of 4Pro Tip 1/3Central Importance Use 'main' to highlight the most critical component or idea in a discussion. The main issue here is communication. Pro Tip 2/3Implicit Hierarchy 'Main' implies other items are secondary or less important. Our main goal is to improve quality. Pro Tip 3/3Preceding Nouns 'Main' often comes before the noun it describes, not after. She lives on the main road, not the side streets.