harlotry: repeated, brazen acts of promiscuous unfaithfulness, pictured as a wife who sells herself to anyone
This word names harlotry, the shameless selling of oneself in promiscuous unfaithfulness. It is built on the verb זָנָה, "to play the harlot," and it appears only in the book of Ezekiel, always in the plural, a form that heaps act upon act into a picture of relentless, repeated betrayal.
Ezekiel uses it inside two extended pictures of a marriage gone wrong. In chapter 16 the city of Jerusalem is a wife whom God rescued, raised, and married, and who then gives herself to every passerby. In chapter 23 two sisters, standing for Samaria and Jerusalem, chase after one lover after another. In both, the harlotry is a metaphor: the covenant people's unfaithfulness to their God.
That unfaithfulness runs in two channels, and the word covers both. One is worship, bowing to idols and other gods instead of the LORD. The other is politics, courting the great powers of the day, Egypt, Assyria, and Babylon, and trusting their strength rather than God's. Ezekiel treats the two as one and the same betrayal: a marriage partner running to other lovers.