However, based on common dictionaries and the definition of a noun as a person, place, or thing, here's a possible contender:
* "abolition" (4 syllables)
While there are shorter 4-syllable words like "abracadabra", they are often considered interjections or onomatopoeia. "Abolition" is a more concrete noun with a clear definition.
Let me know if you'd like to explore other possibilities!