The word "wickedness" is a noun; a word for the quality of a person to be evil or immoral; a word for a thing.
A noun functions as the subject of a sentence or a clause, and as the object of a verb or a preposition.
Example uses:
The profound wickedness of the Witch of the West almost cost Dorothy her life. (subject of the sentence)
The refugees attempted to flee where wickedness couldn't follow. (subject of the adverbial clause)
The crime revealed the wickedness behind her facade. (direct object)
A prison sentence was his reward for wickedness. (object of the preposition)
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