1
general::
For the most part, generally speaking, as in By and large the novel was a success. This expression originated in 17th-century seamanship, where it referred to sailing into the wind and then off it, which made it easier to steer. By the early 1700s the term had been broadened to mean "in one direction and another," whence its present meaning of "in general." For a synonym, see FOR THE MOST PART.
American Heritage Idioms
2
general::
Phrase(s): by and large
generally; usually. (Originally a nautical expression.) • I find that, by and large, people tend to do what they are told to do. • By and large, rosebushes need lots of care.
McGrawhill's American Idioms And Phrasal Verbs