Primitive in this context is closer to innate or previously existing in the person.
Explanation:
Primitive in the sense of psychology for Freud was always something that had existed in the person without any outside influence that would inform their behavior.
The primitive action is one that the person is ingrained to perform in the way of their own psyche and has nothing to do with outside influence over them.
This is developed in the concept of displacement and familiarization of the death principle and the life principle of Freud that is being discussed hire.
