The Collaborative International Dictionary of English v.0.48:

Juxtapose \Jux`ta*pose"\ (j[u^]ks`t[.a]*p[=o]z"), v. t. [Cf.
   Juxtaposit, Pose.]
   To place in juxtaposition. --Huxley.
   [1913 Webster]

WordNet (r) 3.0 (2006):

juxtapose
    v 1: place side by side; "The fauvists juxtaposed strong colors"

Moby Thesaurus II by Grady Ward, 1.0:

57 Moby Thesaurus words for "juxtapose":
   abut, accumulate, adjoin, agglomerate, aggregate, aggroup, amass,
   appose, assemble, batch, bring near, bring together, bulk, bunch,
   bunch together, bunch up, clump, cluster, collect, colligate,
   collocate, combine, compare, compile, conglomerate, corral,
   cumulate, dig up, draw together, dredge up, drive together, gather,
   gather in, gather together, get in, get together, group, join,
   juxtaposit, lump together, make up, mass, match, mobilize, muster,
   neighbor, pair, partner, put together, put with, raise, rake up,
   rally, round up, scrape together, take up, whip in