In the Book of Genesis,
Zilpah (זִלְפָּה "meaning uncertain,"
Standard Hebrew Zilpa,
Tiberian Hebrew Zilpāh) was Leah's handmaid,
Leah gave to
Jacob "to wife" to bear him children (Genesis
Zilpah gave birth to two sons, whom
Leah claimed as her own
and named Gad and
Asher (Genesis 30:10-13).
Zilpah is given to
Leah as a handmaid by Leah's father, Laban, upon
Leah's marriage to
Jacob (see Genesis 29:24, 46:18). According to the
early rabbinical commentary Pirke De-Rabbi Eliezer,
Zilpah and Bilhah,
the handmaids of
Leah and Rachel, respectively, were actually younger
daughters of Laban.
Zilpah also figures in the competition between Jacob's wives to bear
Leah stops conceiving after the birth of her fourth son, at
which point  Rachel, who had not yet borne children, offers her
handmaid, Bilhah, "to wife" to
Jacob so that she can have children
through her. When
Bilhah conceives two sons,
Leah takes up the same
idea and presents
Zilpah "to wife" to Jacob.
Leah names the two sons
Zilpah and is directly involved in their upbringing.
According to Rashi, an 11th-century commentator,
Zilpah was younger
than Bilhah, and Laban's decision to give her to
Leah was part of the
deception he used to trick
Jacob into marrying Leah, who was older
than Rachel. The morning after the wedding, Laban explained to Jacob,
"This is not done in our place, to give the younger before the older"
(Genesis 29:26). But at night, to mask the deception, Laban gave the
veiled bride the younger of the handmaids, so
Jacob would think that
he was really marrying Rachel, the younger of the sisters.
In Jewish tradition,
Zilpah is believed to be buried in the Tomb of
the Matriarchs in Tiberias.
In popular culture
In the novel The Red Tent by Anita Diamant,
represented as half-sisters of
Rachel by different mothers.
^ For the etymology, see: Herbert Lockyer (22 November 2016). All the
Women of the Bible. Zondervan. p. 242.
^ Rabbi Eliezer. "Chapter 36". Pirke De Rabbi Eliezer. Translated by
Friedlander, Gerald (1916 translation ed.). London: Kegan Paul,
Trench, Turner & Co. Ltd. p. 271-272.
^ Genesis 30:3
^ For Rashi's commentary on this, with English translation, see
Rashi's notes on 30:10: 
^ Genesis 20:12:
Sarah was the half–sister of Abraham.
^ Genesis 22:21-22: Uz, Buz, Kemuel, Chesed, Hazo, Pildash, and
Jacob by wife in order of birth
Bilhah (Rachel's servant)
Zilpah (Leah's servant)