The Collaborative International Dictionary of English v.0.48:

Usual \U"su*al\, a. [L. usualis, from usus use: cf. F. usuel.
   See Use, n.]
   Such as is in common use; such as occurs in ordinary
   practice, or in the ordinary course of events; customary;
   ordinary; habitual; common.
   [1913 Webster]

         Consultation with oracles was a thing very usual and
         frequent in their times.                 --Hooker.
   [1913 Webster]

         We can make friends of these usual enemies. --Baxter.
   [1913 Webster] -- U"su*al*ly, adv. -- U"su*al*ness, n.
   [1913 Webster]

WordNet (r) 3.0 (2006):

usually
    adv 1: under normal conditions; "usually she was late" [syn:
           normally, usually, unremarkably, commonly,
           ordinarily] [ant: outstandingly, remarkably,
           unco, unusually]

Moby Thesaurus II by Grady Ward, 1.0:

61 Moby Thesaurus words for "usually":
   accustomedly, again and again, all in all, all things considered,
   altogether, as a rule, as a whole, as an approximation,
   as is usual, as per usual, as things go, as usual, at large,
   broadly, broadly speaking, by and large, chiefly, commonly,
   consistently, conventionally, customarily, frequently, generally,
   generally speaking, habitually, in general, in many instances,
   in the main, inveterately, mainly, many a time, many times,
   most often, mostly, naturally, normally, normatively,
   not infrequently, not seldom, oft, often, often enough, oftentimes,
   ofttimes, on balance, on the whole, ordinarily, overall,
   predominantly, prescriptively, prevailingly, regularly, repeatedly,
   roughly, roughly speaking, routinely, speaking generally,
   to be expected, unseldom, whenever you wish, wontedly