purist

A purist is one who desires that an item remain true to its essence and free from adulterating or diluting influences. The term may be used in almost any field, and can be applied either to the self or to others. Use of the term may be either pejorative or complimentary, depending on the context. Because the appellation depends on subjective notions of what is "pure" as opposed to "adulterating" as applied to any particular item, conflict can arise both as to whether a person so labeled is actually a purist and as to whether that is desirable.