The term "amoralist" typically refers to someone who lacks moral principles or values. However, there are several synonyms that can be used to describe such individuals. One common alternative is "immoralist," which suggests that the person in question deliberately goes against societal standards of what is right and wrong. "Unprincipled" is another option that emphasizes the individual's lack of guiding beliefs or values. "Ethically indifferent" and "amoral" are two more synonyms that carry similar connotations. Overall, these words all suggest a lack of moral grounding and a disregard for conventional standards of behavior.