Sarcastic, satiric, ironic, sardonic can mean having or manifesting bitterness and power to cut or sting.
A person, a mood, a remark, or an expression is sarcastic when he or it manifests an intent to inflict pain by deriding, taunting, or making ridiculous.
A person or his utterance, expression, or spirit is satiric when he or it manifests the intent to censure someone or something by holding him or it up for ridicule and reprobation.
Not only a person or an utterance, mood, or expression but also a situation or an event may be described as ironic when he or it manifests the power to evoke amused but often startled or unpleasant reflection on the difference between what is said and what is intended or between what happens and what was aimed at or what was expected.
A person or more often a person’s smile, expression, or words may be described as sardonic when he or it manifests scorn, mockery, and derision.