Maverick

#019
MAVERICK
A person who thinks and acts in an independent way, often behaving differently from the expected or usual way.
Unbranded, Independent, Odd man out. Black sheep, etc

Ecuador on Thursday granted asylum to maverick WikiLeaks founder Julian Assagne. [From today's Times Of India headlines]
Here TOI has referred to Assagne as Maverick, as he did very different in Journalism, The WikiLeaks.

Origin : 
This is originated from the person, Samuel Maverick.
In Texas ranchers used to brand their cattle to keep one herd separate from others.
And Samuel Maverick refused to do so, as it pains animals.
Hence the word Maverick was applied to all cattle without brands.

Usage :
Mavericks of Indian cinema.
Now a maverick scientist says she may have the answer.