Dastardly Deeds

I remember old cartoons referring to nasty villains perpetrating "dastardly deeds," but I have never heard the word, dastard. Actually, it has just come back to me that the villain that Dudley Dooright was always battling was Dick Dastardly!

Memory is a funny thing.

So I was thinking about the word, dastardly, and thought, it sounds like there must be a word, dastard. So I looked it up in my handy pocket dictionary. Dastard was there, and dastardly, the adjective form was listed within that entry.

Dastard - n. craven coward or deceitful sneak.

It seems to come from Middle English. I wonder if it is related to another very similar word which starts with "B?"