Etymologically, from words for "doubt" or "error" or "deadly nightshade". ('I thought they were huckleberries', dwaled Tom.) Or, black, in a floriferous system of heraldic tinctures; or, a sleeping potion or opiate; all according to Dictionary.com.
Oops; I thought it was an archaic form of 'dwindle'.
I wonder if the heraldic tinctures-by-plants was for doing heraldry out in bedding-plants. Belladonna isn't perfectly black, but it might have been one of the blackest-leaved plants available a hundred years ago. When did the foliage-fanciers start searching for dark materials?
So wrote clew in Word. | TrackBack