Concubine

And his concubine,
whose name was Reumah,
she bare also Tebah,
and Gaham,
and Thahash,
and Maachah.
Genesis 22:24 KJV

And it came to pass,
when Israel dwelt in that land,
that Reuben went and lay with Bilhah his father's concubine:
and Israel heard it.
Now the sons of Jacob were twelve:
Genesis 35:22 KJV

And Timna was concubine to Eliphaz Esau's son;
and she bare to Eliphaz Amalek:
these were the sons of Adah Esau's wife.
Genesis 36:12 KJV