The Oxford Thesaurus An A-Z Dictionary of Synonyms - dummy n.

1) mannequin, manikin or mannikin, model, figure: I saw the coat on a dummy in the shop window. 2) sample, copy, reprint, reproduction, likeness, substitution, imitation, sham, mock-up, simulation, Colloq phoney or US also phony: Those aren't the real crown jewels, they're just dummies. 3) fool, idiot, dunce, blockhead, ninny, ass, dolt, numskull or numbskull, simpleton, Colloq dim-wit, US thimble-wit: They're such dummies they don't know that you're joking. 4) US pacifier: Give the baby the dummy to suck.