Mordantly is an adverb that describes a dry and biting sense of humor or wit. Some synonyms for mordantly include acerbically, caustically, bitingly, sardonically, sarcastically, cuttingly, acidly, and pungently. Each of these words has a distinct nuance but they all embody the same sense of sharp and incisive humor. Acerbically is often used to describe a speech that is harsh and critical. Caustically carries the connotation of a corrosive or burning quality. Sardonically is typically used when the humor is mocking or cynical. Sarcastically generally refers to a comment that is intended to be ironic or satirical. Cuttingly often implies cruelty or harshness. Acidly is good to use when the humor is sour or bitter, and pungently is typically associated with a strong, penetrating smell.