"Dastard" is a proper English rude word, albeit pretty archaic...
[backslash]Das"tard[backslash], n. [Prob. from Icel. d[ae]str exhausted. breathless, p. p. of d[ae]sa to groan, lose one's breath; cf. dasask to become exhausted, and E. daze.] One who meanly shrinks from danger; an arrant coward; a poltroon.
You are all recreants and dashtards, and delight to live in slavery to the nobility. --Shak.
Source: Webster's Revised Unabridged Dictionary, ? 1996, 1998 MICRA, Inc.
J-Bo-you-wouldn't-have-thought-Shak-was-that-verbose-if-you'd-sat-through-STEEL-1