Were the Buddha's earliest followers bhikkhus? What is the proper name for the Buddha's earliest followers such as Ananda and Sariputta - the ones that followed the Buddha during his lifetime. Would the term be bhikkhu and  bhikkhuni or does this only apply to settled monastics?
There are 4


Bhikkhu - Male monk
Bhikkhuni - Female nun
Upasaka - Lay male follower
Upasika - Lay female follower


Also note that in the Suttas all of the above are referred as Bhikkhus in addressing.