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Which? Low refresh rate leads to high latency, but you can have high latency without a low refresh rate also.
Blur is a different thing. If you get blur, then each individual image looks... blurry. You can have no blur but high latency, or you can have a lot of blur with low latency. They can be connected but they aren't the same thing.
Just to clarify, it's not really blur but ghosting. It means the last frame is still fading off the screen when the next frame goes live. It means you get an overall blur effect. It used to be extremely bad a few years ago but the faster response times of modern tft screens has meant you hardly see ghosting these days.
Refresh rate is the number of frames shown per second. Usually it's around 75Hz max on tft.
Latency is the delay between stuff actually happening and it being shown on the screen. There's a video somewhere showing a particularly bad tft that has high latency, sitting next to a crt with very low latency. You can see stuff happening on the tft a few frames later.