The phrase "a certain cool" is correct and usable in written English.
It can be used to describe a specific level of coolness or style that is notable or distinctive.
Example: "She has a certain cool that makes her stand out in any crowd."
Alternatives: "a particular coolness" or "an undeniable cool".
Even the president's most avid critics admit he exudes a certain cool confidence.
But liberal Web sites like The Huffington Post now have vast followings of young people and a certain cool factor — something many advertisers value over intellectual prestige.
As an admirer observed, Mr. Marks was a bit like an oyster himself: "hard shell, compact build, self-sufficient, a certain cool acidity".
The explosion of "geek" and "nerd" slogan T-shirts in the last couple of years has encouraged a certain cool factor for developers and programmers.
While spring festivals occur all over the country, Hoboken's possesses a certain cool veneer that most other street fairs do not.
Well, assuming it gets built (Boeing still hasn't made a final decision), the jet will have a certain cool factor, because Boeing plans to make it out of composites instead of aluminum, which is what most jets are made of.
But, if this suggests a certain cool-dude, second-generation irreverence for parental favorites, there is no trace of cheekiness on the opening track of "El Cancionero" — a loving and disarmingly pretty version of "Guantanamera".
A critical cooling flow rate Lc exists under a certain heat flux for a certain cooling system.
The PWR spent fuel will be transferred directly (after a certain cooling time) to CANDU reactors which preferably built in the same site to avoid the problem of transportations.
The recipe may make a certain cooling method apparent and this should be followed to ensure the outcome promised by the recipe.
Mr. Manilow seems as ripe as anyone to travel the path from hopelessly outdated singer to retro star with, yes, a certain kitschy cool.
