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.
Unique does not mean "Come to our store where you and 5 billion other people can buy the same exact unique item." It's over-used in ads, newscasts, and printed media.
A friend of mine used to say "It's the most unique thing I have ever seen!"
Our other friend, the grammar cop, finally said "Is it more unique than the most unique thing you saw LAST week?"
Most unique is like absolutely final. Both words are definitive... they can't be modified.
Thank you! This is one of mine too. "Our cupcakes will have more unique flavors than..." NO THEY WON'T. They can have unusual, rare, uncommon, special, different, surprising flavors. But they do not, will not, and cannot have, more unique flavors, because unique has no gradations. The phrasing is further undermined to a teeth-gritting degree when the "unique" flavor is something like salted caramel or mocha strawberry, which maybe not everybody has come up with, but certainly more than one individual has.
DH just rolls his eyes now when I start shouting "Non-modifiable adjective!" at the television. I think he's finally gotten used to me arguing with cooking shows.