- spider. This old name for a spider appears in English as attercop. Atter or etter is suppurating matter, so this is not a very pretty name. The form nettercap comes from a confusion of word division in an ettercap. A similar thing has happened, in the opposite direction, with the modern English word adder and Scots word eddir which derive from an earlier form, nedder.
Ettercap could be applied to a person with a poisonous disposition.