Reply #105: not exactly, different connotation

[gejohnston]

exceptional implies superiority while unique is simply one of a kind

ex·cep·tion·al   
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–adjective
1.
forming an exception or rare instance; unusual; extraordinary: The warm weather was exceptional for January.
2.
unusually excellent; superior: an exceptional violinist.
3.
Education . (of a child)
a.
being intellectually gifted.
b.
being physically or especially mentally handicapped to an extent that special schooling is required.



u·nique   
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–adjective
1.
existing as the only one or as the sole example; single; solitary in type or characteristics: a unique copy of an ancient manuscript.
2.
having no like or equal; unparalleled; incomparable: Bach was unique in his handling of counterpoint.
3.
limited in occurrence to a given class, situation, or area: a species unique to australia.
4.
limited to a single outcome or result; without alternative possibilities: Certain types of problems have unique solutions.
5.
not typical; unusual: She has a very unique smile.