The definition of a main is a primary line used for distributing water, gas and electricity.(noun)
An example of a main is an underground pipe that brings water to a building.
Main is described as the most important or primary person or thing.(adjective)
An example of main is a main character, such as Tom Sawyer being the primary character in the book The Adventures of Tom Sawyer.
See main in Webster's New World College Dictionary
Origin: < mainthethe principal or most important part or point: usually in the phrase , mostly, chiefly
Origin: ME < OE mægen, akin to ON magn: see might
Origin: ME mayn < OE mægen- (in comp.) & ON meginn, strong
Origin: G < Gaul Moenus < IE *moin-, river name < base *mei-, to go, wander > L meare, to go
See main in American Heritage Dictionary 4
Origin: Middle English
Origin: , from Old English mǽgen, strength; see magh- in Indo-European roots.
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