Which word describes a person who can be seen as bitterly mocking?

The term "sardonic" effectively captures the essence of someone who exhibits a bitterly mocking demeanor. It conveys a sense of disdainful or grimly sarcastic humor, often characterized by a cutting wit that aims to deride or scorn someone or something. Individuals who are sardonic may express their thoughts through sharp remarks or an overall sense of cynicism, which aligns well with the idea of being bitterly mocking.

In contrast, the other terms do not possess this meaning. "Amicable" describes a friendly or pleasant disposition, which is the opposite of being mocking. "Sympathetic" indicates a feeling of compassion or understanding towards others, again not aligning with a mocking attitude. Lastly, "regretful" signifies feelings of sorrow or remorse, which does not fit the concept of bitterness or mockery. Therefore, "sardonic" is the most appropriate choice as it directly reflects the idea of a twisted, satirical form of humor that can sting, making it the correct answer.