What was the name of the prophet Hosea's wife?

Answer: Gomer

God told Hosea to marry an unfaithful wife as a picture of Israel's unfaithfulness, so he married Gomer daughter of Diblaim.

“When the LORD first spoke through Hosea, He told him, “Go, take a prostitute as your wife and have children of adultery, because this land is flagrantly prostituting itself by departing from the LORD.” So Hosea went and married Gomer daughter of Diblaim, and she conceived and bore him a son.”— Hosea 1:2-3 (BSB)