If so, then the only camera I can think of that *might* qualify is a Panasonic FZ200. While it has a relatively small (1/2.3") sensor, it might fit into a larger purse, and you might be able to find one for around $400 since the successor model is due out soon.
If you can increase your budget to around $600 and are willing to sacrifice zoom ratio (4X), the Canon G7X has a larger 1" sensor, while the camera itself is actually smaller and will fit into a clutch, maybe with room leftover for a lipstick. (Full disclosure: I own one.)
Or if you can increase your budget to around $800 and are willing to sacrifice size (to shoulder bag, at the minimum), the Panasonic FZ1000 has a large 1" sensor and 16X (f2.8-4.0) zoom.
Or if you don't need low light performance when zoomed in (i.e. only when zoomed out/wide angle), you could probably pick up an older model Sony RX100 within your budget which will have a 1" sensor and be similar in size to the Canon G7X.
Could someone recommend a quality low light camera with a good size CMOS for grain free pics. It should fit in a woman's purse and have a decent zoom ratio. It should be priced between $250-$400. Thanks as this will be a present for my wife who has a fair knowledge of photography.

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