adj. 1 chief, primary, prime, (most) important, principal, cardinal, paramount, first, foremost, leading, pre-eminent, predominant, predominating, dominant, ranking, major; outstanding The main cause of traffic deaths is drunken driving In Britain, the main street of a town is called 'the High Street'. We arrived late and missed the main entertainment. 2 largest, biggest, greatest, strongest The main part of the strike force landed in Normandy 3 necessary, essential, basic, particular, fundamental, critical, crucial, vital Economic recovery is the main thrust of our programme for reform 4 sheer, brute, utter, pure, out-and-out, absolute, mere, plain He lifted that block by main force!
n. 5 pipe, duct, channel, line, pipeline, water or gas main, Brit (electric) cable, mains, power (supply), conduit Water reaches the city through a huge underground main 6 strength, power, might, effort, energy, vigour With all his might and main he tried to move the stone blocking the cave 7 in the main. See mainly, below.