Genesis 38:14-15

38:14 So she removed her widow’s clothes and covered herself with a veil. She wrapped herself and sat at the entrance to Enaim which is on the way to Timnah. (She did this because she saw that she had not been given to Shelah as a wife, even though he had now grown up.)

38:15 When Judah saw her, he thought she was a prostitute because she had covered her face.