With all one's might and main

Main Main, n. [AS. m[ae]gen strength, power, force; akin to OHG. magan, Icel. megin, and to E. may, v. [root]103. See {May}, v.] 1. Strength; force; might; violent effort. [Obs., except in certain phrases.] [1913 Webster]

There were in this battle of most might and main. --R. of Gl. [1913 Webster]

He 'gan advance, With huge force, and with importable main. --Spenser. [1913 Webster]

2. The chief or principal part; the main or most important thing. [Obs., except in special uses.] [1913 Webster]

Resolved to rest upon the title of Lancaster as the main, and to use the other two . . . but as supporters. --Bacon. [1913 Webster]

3. Specifically: (a) The great sea, as distinguished from an arm, bay, etc.; the high sea; the ocean. ``Struggling in the main.'' --Dryden. (b) The continent, as distinguished from an island; the mainland. ``Invaded the main of Spain.'' --Bacon. (c) principal duct or pipe, as distinguished from lesser ones; esp. (Engin.), a principal pipe leading to or from a reservoir; as, a fire main. [1913 Webster]

{Forcing main}, the delivery pipe of a pump.

{For the main}, or {In the main}, for the most part; in the greatest part.

{With might and main}, or {With all one's might and main}, with all one's strength; with violent effort. [1913 Webster]

With might and main they chased the murderous fox. --Dryden. [1913 Webster]