The Hebrew Bible gives Jezebel almost no interior life; she exists in the text as an instrument of royal policy and a target of prophetic judgment, and the account that survives is the Deuteronomistic history's, written by scribes hostile to the northern kingdom and to the Baal cult she promoted. Modern historians read her with that authorship in view: the extent to which the biblical Jezebel reflects a real ninth century queen's actual conduct, as opposed to a literary villain built to explain Israel's religious failures, is a genuine point of scholarly disagreement rather than a settled biography.
Her name outlived the specifics of her story. The Book of Revelation addresses a prophetess at the church of Thyatira and calls her "Jezebel," accusing her of teaching believers to commit sexual immorality and eat food sacrificed to idols, extending the name from a ninth century Israelite queen to a first century Christian rival teacher a thousand years and a different religion apart, which shows how quickly the name had become a generic label for a corrupting religious woman rather than a reference to the historical figure herself.
By the time the word entered common English usage, "jezebel" had detached from the narrative altogether and became a byword for a sexually forward, manipulative or shamelessly self-adorned woman, a usage that says considerably more about the cultures that repeated it than about the historical or literary Jezebel. Recent feminist and postcolonial readings have pushed back on that flattening, arguing that a foreign born queen defending her own religion against a rival state cult, in a text written entirely from her enemies' side, deserves a harder look than the epithet allows.