Monosyllabic refers to one single syllable. Mono means one, for example, the word "go" is monosyllabic, because it has only one syllable. Polysyllabic refers to words that have three or more syllables, poly means many, for example, the word "evolution" is polysyllabic. disyllable means two syllables. In fact, this website has a complete explanation of questions you asked. See the following website:
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