Unique may be the foremost example of the absolute term?a term that, in the eyes of traditional grammarians, should not allow comparison or modification by an adverb of degree like very, somewhat, or quite. Thus, most grammarians believe that it is incorrect to say that something is very unique or more unique than something else, though phrases such as nearly unique and almost unique are acceptable, since in these cases unique is not modified by an adverb of degree. Most of the Usage Panel supports the traditional view. Eighty percent of the panelists disapprove of the sentence Her designs are quite unique in today?s fashion.    1
  Some criticism of the comparison and modification of unique no doubt stems from the word?s use?and overuse?in advertising. For unique is everywhere. Who has not seen it in ad copy such as Our city?s most unique restaurant is now even more unique or in claims like that for the automobile that is So unique, it?s patented? In these examples unique is used as a classy-sounding synonym for unusual or distinctive.    2
  But if you can?t escape the modification of unique in advertisements, you are also likely to find it in the work of many reputable writers, though without the exaggeration. When an art critic describes the most unique of Beckman?s self-portraits, and a travel writer states that Chicago is no less unique an American city than New York or San Francisco, it is hard to see what is out of joint here. After all, if we were to use unique only according to the strictest criteria of logic, we might freely apply the term to anything in the world, since nothing is wholly equivalent to anything else. Clearly, then, when we say that a restaurant or painting is unique, we mean that it is in a class by itself. It might be easier to recognize that unique, like many absolute terms, has more than one sense and can be modified with grace in certain uses. For more on absolute terms, see absolute terms under Grammar.    3
  More at complete, equal, infinite, parallel, and perfect.    4