English dictonaries provide such concrete definitions so that we do not need, as a separate group, to create definitions for our own use or debate the meaning of words.http://dictionary.reference.com/browse/++evil
3.characterized or accompanied by misfortune or suffering.
10.anything causing injury or harm
The word has defined meanings totally independent of philosophical dependency.
Well, "injurious", "misfortune", "suffering" and "harm" seem somehow quite context-sensitive to me (maybe just because I studied too much of theology).
The dictionary provides several "definitions" of the term "evil", particularly those most commonly used when "evil" is used. To do so, it obviously needs at least 10 different "definitions".
From a philosophic logical perspective, it provides the most likely extension of the term, i.e. examples of what people "typically" mean, when they use the word "evil". However, the editors know, that this is not enough. To help the reader find an acceptable meaning of the term, they give further hints, like homonymes, example sentences, and - very important - the term's ethymology und history of its meaning in literature und the language's history. This is all about providing context, to the reader who, for a concrete situatioin - has to decide which meaning the used term has, or whether an idea he wants to express using the term is likely understandable in a given certain context.
This is required, just because the word itself has no clear meaning at all.
Hence, while using a dictionary to clarify the meaning of a word is a nice idea, but actually does not solve the problem. Any dictionary entry provides a partial history on previous logical games played to capture the meaning of a term. It does provide a subset of the term's extension, but does not properly define the intension of the term in any exact way. This is due to the fact, that the meaning of a term like "evil" is never fixed at all. It's ever changing.
Part of this problem is that dictionaries (and philosophers) depend on using language relying on terms to communicate their ideas about the meaning of terms, which does not lessen the problem. Every translator - actually any user of language - deals with that problem day by day, when he tries to explain what he actually wants to express exactly
. And it took philosophy no more than some thousand years to discover this to be a real unsolvable problem - and that this is actually part of all the fun with it.
Other, pure axiomatic languages, as mathematic notations, avoid this problem, but only for the price of a quite limited expressiveness. This is part of what Wittgenstein discovered between the "Tractatus Logico-Philosophicus" and his "Philosophical Investigations".
I do not say, that it is fruitless to have discussions on the meaning of terms - on the contrary: it is a quite necessary process. I just say, that we will not come to a definite end with it.