Definitions

1. adjective

keenly perceptive and often caustic in judgment or comment

“He delivered a mordant critique of the film’s portrayal of social issues.”

2. noun

a caustic or biting quality or comment

“The mordant wit of the comedian left the audience in stitches.”

3. noun

a substance used in dyeing, especially a strong acid or a salt that can give a dye its color

“The mordant used in the dyeing process helped to create a unique shade of blue.”