MAIN (3)

Main (?), a. [[From Main strength, possibly influenced by OF. maine, magne, great, L. magnus. Cf. Magnate.]] 1. 1. Very or extremely strong.
That current with main fury ran. Daniel. 2. 2. Vast; huge. “The main abyss.” Milton.
3. 3. Unqualified; absolute; entire; sheer. “It's a man untruth.” Sir W. Scott.
4. 4. Principal; chief; first in size, rank, importance, etc.
Our main interest is to be happy as we can. Tillotson. 5. 5. Important; necessary.
That which thou aright Believest so main to our success, I bring. Milton. By main force, by mere force or sheer force; by violent effort; as, to subdue insurrection by main force. That Maine which by main force Warwick did win. Shak. — By main strength, by sheer strength; as, to lift a heavy weight by main strength. — Main beam (Steam Engine), working beam. — Main boom (Naut.), the boom which extends the foot of the mainsail in a fore and aft vessel. — Main brace. (a) (Mech.) The brace which resists the chief strain. Cf. Counter brace. (b) (Naut.) The brace attached to the main yard. — Main center (Steam Engine), a shaft upon which a working beam or side lever swings. — Main chance. See under Chance. — Main couple (Arch.), the principal truss in a roof. — Main deck (Naut.), the deck next below the spar deck; the principal deck. — Main keel (Naut.), the principal or true keel of a vessel, as distinguished from the false keel. Syn. — Principal; chief; leading; cardinal; capital.