The Collaborative International Dictionary of English v.0.48:

En bloc \En` bloc"\ [F. Cf. Block, n. ]
   In a lump; as a whole; all together. "Movement of the
   ossicles en bloc." --Nature.

         En bloc they are known as "the herd".    --W. A.
                                                  Fraser.
   [Webster 1913 Suppl.]

WordNet (r) 3.0 (2006):

en bloc
    adv 1: all together; "the students turned out en masse" [syn:
           en masse, en bloc, as a group]

Moby Thesaurus II by Grady Ward, 1.0:

26 Moby Thesaurus words for "en bloc":
   across the board, all, all put together, altogether, as a body,
   as a whole, at large, bodily, collectively, corporately, en masse,
   entirely, in a body, in all, in all respects, in bulk,
   in its entirety, in the aggregate, in the gross, in the lump,
   in the mass, in toto, on all counts, totally, tout ensemble,
   wholly