I saw some TVs from LG have MCI (Motion Clarity Index), like MCI 100.
What does the 100 mean? 100Hz refresh rate maybe?
To some extent you’re right, yet MCI is not directly linked with refresh rate though it has to work in the same area but MCI pattern is quite different from refresh rate.
Basically refresh rate technology is meant for faster image production on screen however, MCI along with faster image production at the same time also responsible for reducing the blur from fast moving action scenes and enhances the clarity of image far more than before.
Technically speaking - saying 100MCI = 100Hz is not justifiable at all, though we can just assume that this figure is referring us to the number of frames at which the image gets incorporated on screen.