Main Definition

mān

adjective

Most important; principal.

American Heritage

Strong; powerful.

Webster's New World

Exerted to the utmost; sheer.

American Heritage

Chief in size, extent, importance, etc.; principal; leading; specif., designating a large central unit on which subsidiaries or branches depend.

The main post office.

Webster's New World

Of, near, or connected with the mainmast or mainsail.

Webster's New World

Synonyms:

Antonyms:

noun

The principal or most important part or point.

Webster's New World

Physical strength; force; power.

Webster's New World

A principal pipe, conduit, or line in a distribution system for water, gas, electricity, etc.

Webster's New World

The mainland.

Webster's New World

The high, or open, sea; ocean.

Webster's New World

Synonyms:

pronoun

A river in southern Germany, flowing from Bavaria to the Rhine.

Wiktionary

adverb

Wiktionary

Other Word Forms of Main

Singular:

main

Plural:

From Middle English main, mayn, meyn, partly from Old English mægen- ("strong, principal, main"; used in combination), from Old English mæġen (“strength"), and partly from Old Norse megn, megenn (“strong, main"); both from Proto-Germanic *maginÄ… (“strength, power, might"), *maginaz (“strong"), from Proto-Indo-European *mogh-, *megh- (“power"). Cognate with Old High German megÄ«n (“strong, mighty"), German Möge, Vermögen (“power, wealth"). Akin also to Old English magan (“to be able to"). More at may.

From Wiktionary
Middle English from Old English mægen strength magh- in Indo-European roots

From American Heritage Dictionary of the English Language, 5th Edition
From Old English mægen (“strength"), later also taking senses from the adjective.

From Wiktionary
French main (“hand"); compare manual.

From Wiktionary