Who was Orpah?
Orpah was the daugher of Naomi and the sister of Ruth.
Orpah was a Moabitess, wife of Mahlon, son of Elimelech and Naomi. Unlike her sister Ruth she returned to her own people after escorting Naomi on her way to Judah (Rth 1:4 ff).
Her name is supposed to be derived from the Hebrew word for "neck," and so to mean "stiff-necked" because of her turning-back from following her mother-in-law; others take it to mean "gazelle.
IBSE, "Isaac" (in the public domain) with minor edits.