Word to the Wise: Dastard
A "dastard" (DAS-terd) is a mean, sneaky coward. The word may have been derived from "dast/dased," Middle English for "stupid" or "dull."
Example (as used in Time magazine): "Even that notorious dastard and Spanish Political Grafter Juan March, popularly supposed to get his way in any part of Spain with 1,000 peseta notes, bolted like a rabbit for France until things should quiet down."