What is "poemen"

Abba Poemen ( Greek: Ὁ Ἅγιος Ποιμήν; ποιμήν means "shepherd") (c. 340–450) was an Egyptian monk and early Desert Father who is the most quoted Abba (Father) in the Apophthegmata Patrum (Sayings of the Desert Fathers). Abba Poemen was quoted most often for his gift as a spiritual guide, reflected in the name "Poemen" ("Shepherd"), rather than for asceticism. He is considered a saint in Eastern Christianity. His feast day is August 27 in Julian calendar (September 9 in Gregorian calendar).