What does Genesis 30:18 mean?

Leah and her sister Rachel are engaged in a "birth race," competing for personal pride and for the affection of their mutual husband, Jacob. Leah initially was able to bear four children of her own (Genesis 29:31–35), before Rachel seems to have jealously convinced Jacob to stop sleeping with her. Rachel, on her part, was unable to have her own children, so she obtained two through her female servant, Bilhah. Leah had seen this and responded in kind, producing two more sons through her servant Zilpah. When Leah's oldest child found fertility-enhancing mandrakes, Leah sold some of them to Rachel with the understanding that Leah be allowed to sleep with Jacob for a night (Genesis 30:14–17). The result of that sale is another natural son for Leah, her fifth, her seventh combined, and Jacob's ninth son overall.

Leah names this son based on her understanding that God is repaying her for giving her servant Zilpah to Jacob as a wife. That seems to indicate that Leah saw this sharing of Zilpah with Jacob, even for the sake of having more sons, as a sacrificial act for the better good of Jacob. The name Yissaskar is similar to the word used in this verse for wages, sakar, so the name might also mean "my hire" or "man of hire," referring to the night with Jacob that Leah bought by giving her mandrake plants to Rachel. Alternatively, the name may mean "may God be gracious."