Main adj. 1.Very or extremely strong. (Obs.) "That current with main fury ran."
2.Vast; huge. (Obs.) "The main abyss."
3.Unqualified; absolute; entire; sheer. (Obs.) "It's a man untruth."
4.Principal; chief; first in size, rank, importance, etc.; as, the main reason to go; the main proponent. "Our main interest is to be happy as we can."
5.Important; necessary. (Obs.) "That which thou aright Believest so main to our success, I bring."
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."
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.
Synonyms: Principal; chief; leading; cardinal; capital.
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