The same or virtually the same. For example, He's resigning? I thought as much means I thought he was doing just that. [Late 1300s] Also see as much as.
Words nearby as much
The American Heritage® Idioms Dictionary Copyright © 2002, 2001, 1995 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company.