http://www.google.com/search?sourceid=navclient&ie=UTF-8&rlz=1T4GGLL_enUS349US349&q=What+is+a+low+fast+batted+baseball+called%3f
With no conditions except batted, low, and for some reason fast-I would say a "line drive". Maybe a sinking line drive.
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Other people asked questions on various topics, and are still waiting for answer. Would be great if you can take a sec and answer them