47 Moby Thesaurus words for "synonym":
Doppelganger, actual thing, antonym, articulation, carbon copy,
copy, dead ringer, ditto, double, duplicate, equivalent,
exact counterpart, expression, facsimile, free form, homograph,
homonym, homophone, idem, identical same, lexeme, linguistic form,
locution, logos, metonym, minimum free form, monosyllable,
no other, none other, polysyllable, replica, selfsame,
spit and image, spitting image, syllable, term, the same,
the same difference, twin, usage, utterance, verbalism, verbum,
very image, very same, vocable, word



-- From Moby Thesaurus II by Grady Ward, 1.0