Synonyms for Main:

adj.

all (adjective)
independent.
bigger (adjective)
major.
central (adjective)
core, interior, median, focal, central, midway, midmost, nuclear, innermost, pivotal, middle, halfway.
important (adjective)
major.
principal, predominant (adjective)
foremost, prime, major, primary, central, paramount, premier, cardinal, leading, chief, capital.

n.

blockage, carry, airlock, culvert, downspout, conduit, clog, cutoff, cesspit, back up. elementary, foremost, top, number one, key, paramount, basic, first, prime, cardinal, major, leading, capital, premier. main (noun)
intense, independent, primary, of import, important, chief, principal, briny.
ocean (noun)
brink, ocean, brine, sea, deep.
passage (noun)
conduit.
pipe for system (noun)
conduit.
principal (noun)
foremost, study at principal.

Other synonyms:

cardinal, premier. foremost, leading, key, paramount. first, prime. basic. top. pipe
conduit.
principal
capital, principal.

Usage examples for main

  1. Moreover, they are speaking as, in the main those who are fully acquainted with the Christian position, having once occupied it. – A Grammar of Freethought by Chapman Cohen
  2. I've got a clear conscience; that's the main thing. – Project Gutenberg, Deep Waters, by W.W. Jacobs by W.W. Jacobs
  3. Their main object was to see that the work which was turned out was good. – John and Betty's History Visit by Margaret Williamson