Contrary to popular opinion among non-Yorubas and some Nigerians or Africans who does not understand this word, akata does not mean coton picker or slave and it is not derogatory.
It means a cat that doesn't live at home like a wild non domesticated cat, this is used to reference mostly African Americans as they are considered Africans by all Africans but the fact that they don't live in Africa make them akata while those of us who live at home can be considered as Ologbo (cat).
It is no different from an African American calling his buddies "cat" , it is just that the Yorubas recognize the fact that this is a cat that isn't at home.
I am Yoruba who also studied Yoruba in high school and have a better understanding of this word than any none Yoruba or Yoruba who have never studied Yoruba as a language.
It is also another word used to identify Africans who have visited America.
On a recent visit back to Nigeria, a friend was asked about the Iraq war and he directed the question to his friend another Nigerian who was visiting home from America.
" why are you asking me that?, ask the akata here , he can answer it"
The Nigerian have also become an akata because he no longer lives at home.
This is a Yoruba word and only a Yoruba can truly know what it means, for more information search online for Yoruba dictionary, then email the Yorubas listed on the contact page for meaning of akata and they may be able to help you further.