WordNet (r) 3.0 (2006):

by and large
    adv 1: usually; as a rule; "by and large it doesn't rain much
           here" [syn: by and large, generally, more often than
           not, mostly]

Moby Thesaurus II by Grady Ward, 1.0:

36 Moby Thesaurus words for "by and large":
   all in all, all things considered, almost entirely, altogether,
   approximately, as a rule, as a whole, as an approximation,
   at large, broadly, broadly speaking, chiefly, commonly,
   effectually, en masse, essentially, generally, generally speaking,
   in general, in the main, mainly, mostly, normally, on balance,
   on the whole, ordinarily, overall, predominantly, prevailingly,
   roughly, roughly speaking, routinely, speaking generally,
   substantially, usually, virtually