Discreditor is a noun that refers to someone or something that discredits or undermines the reputation of another. The word is spelled phonetically as /dɪsˈkrɛdɪtər/. The prefix "dis-" means "not" or "opposite of," while the root word "credit" means "reputation" or "trustworthiness." The suffix "-or" is used to indicate someone or something that performs an action. Therefore, a discreditor is someone or something that causes a loss of reputation or trustworthiness in someone or something else.