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Main (mān, mīn)
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A river rising in eastern Germany and flowing about 525 km (325 mi) generally westward to the Rhine River at Mainz.

The American Heritage® Dictionary of the English Language, Fifth Edition copyright ©2017 by Houghton Mifflin Harcourt Publishing Company. All rights reserved.
 
main (mān)
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adj.
1. Most important; principal. See Synonyms at chief.
2. Exerted to the utmost; sheer: "They took her off the sled by main strength" (Jack London).
3. Nautical Connected to or located near the mainmast: a main skysail.
4. Obsolete Of or relating to a continuous area or stretch, as of land or water.
n.
1. The chief or largest part: His ideas are, in the main, impractical.
2. The principal pipe or conduit in a system for conveying water, gas, oil, or other utility.
3. Physical strength: fought with might and main.
4. A mainland.
5. The open ocean.
6. Nautical
a. A mainsail.
b. A mainmast.
7. The main dish of a meal: "Unsurprisingly, the mains and their house-made condiments were the standouts of a recent meal" (Lindsey Tramuta).

[Middle English, from Old English mægen, strength; see magh- in the Appendix of Indo-European roots.]

The American Heritage® Dictionary of the English Language, Fifth Edition copyright ©2017 by Houghton Mifflin Harcourt Publishing Company. All rights reserved.
 

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