Similar in meaning, but slightly stronger:
* Unprincipled: This implies a lack of ethical standards, suggesting someone is willing to act against them for personal gain.
* Immoral: This is a more direct synonym, emphasizing the lack of morality in actions or behavior.
* Unethical: This focuses on the violation of ethical principles, often in a professional context.
Less strong, emphasizing neutrality:
* Non-moral: This suggests a lack of concern for morality, rather than a conscious rejection of it.
* Value-neutral: This implies a lack of judgment about right or wrong, often used in the context of scientific or objective observation.
* Unscrupulous: This suggests a willingness to act without regard for ethical considerations.
The best synonym for "amoral" will depend on the specific context and the message you want to communicate.