The Collaborative International Dictionary of English v.0.48:

Crosier \Cro"sier\ (kr?"zh?r), n. [OE. rocer, croser, croyser,
   fr. croce crosier, OF. croce, croche, F. crosse, fr. LL.
   crocea, crocia, from the same German or Celtic sourse as F.
   croc hook; akin to E. crook.]
   The pastoral staff of a bishop (also of an archbishop, being
   the symbol of his office as a shepherd of the flock of God.
   [1913 Webster]

   Note: The true shape of the crosier was with a hooked or
         curved top; the archbishop's staff alone bore a cross
         instead of a crook, and was of exceptional, not of
         regular form. --Skeat.
         [1913 Webster]

WordNet (r) 3.0 (2006):

crosier
    n 1: a staff surmounted by a crook or cross carried by bishops
         as a symbol of pastoral office [syn: crosier, crozier]

Moby Thesaurus II by Grady Ward, 1.0:

41 Moby Thesaurus words for "crosier":
   Malacca cane, alpenstock, baton, caduceus, cane, chain of office,
   crook, cross, cross-staff, crutch, crutch-stick, fasces, gavel,
   handstaff, keys, lituus, mace, mantle, miter, pallium,
   pastoral staff, paterissa, portfolio, quarterstaff, red hat, ring,
   rod, rod of office, scepter, shillelagh, staff, stave, stick,
   swagger stick, swanking stick, tiara, triple crown, truncheon,
   walking stick, wand, wand of office