The practice, principle, or tendency of being a dummy or using dummies; reliance on artificial substitutes (rare).
From 'dummy' plus the suffix '-ism', which creates nouns for ideologies, practices, or systems. This is an extremely rare coinage that doesn't appear in most standard dictionaries.
The '-ism' suffix normally creates ideologies (fascism, socialism), but it can also name practices. 'Dummyism' is so rare that it's essentially a joke word—the kind of thing humorously invented but not actually used!
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