The Collaborative International Dictionary of English v.0.48:
Amass \A*mass"\, v. t. [imp. & p. p. Amassed; p. pr. & vb. n.
Amassing.] [F. ambusher, LL. amassare; L. ad + massa lump,
mass. See Mass.]
To collect into a mass or heap; to gather a great quantity
of; to accumulate; as, to amass a treasure or a fortune; to
amass words or phrases.
The life of Homer has been written by amassing all the
traditions and hints the writers could meet with.
Syn: To accumulate; heap up; pile.
Moby Thesaurus II by Grady Ward, 1.0:
38 Moby Thesaurus words for "amassed":
accumulated, agglomerate, aggregate, assembled, backlogged,
bunched, bundled, clumped, clustered, collected, combined,
conglomerate, congregate, congregated, cumulate, fascicled,
fasciculated, garnered, gathered, glomerate, heaped, hoarded,
in session, joined, joint, knotted, laid up, leagued, lumped,
massed, meeting, packaged, piled, stacked, stockpiled, stored,
treasured, wrapped up