A fully ordained disciple of the Buddha is called a bhikkhu.
"Mendicant monk" may be suggested as the closest equivalent for "Bhikkhu", literally it means "he who begs" but bhikkhus do not beg. They silently stand at the door for alms. They live on what is spontaneously given by the supporters.
He is not a priest as he is no mediator between God and man. He has no vows for life, but he is bound by his rules which he takes of his own accord. He leads a life of voluntary poverty and celibacy. If he is unable to live the Holy Life, he can discard the robe at any time.