Definition of Karateka 

a practitioner of Karate

We have always called folks the study and practice of Karate (irregardless of what style), we called Karate-Ka.  This means that you learn, practice and utilize the set postures, transitions and Kata in self defense type drills and testing.  However in Kumite or free sparring, these are not utilized as it is only an exchange of punches and kicks, sometimes take-downs and blocks.