Refresh rate is a characteristic of computer display monitors and projection devices that defines the frequency and ability of the device to repaint or redraw the entire visible display on the screen each second.
Refresh rate is measured in hertz and will vary according to the architecture of the display device.
Refresh rate is also known as vertical refresh rate or vertical scan rate.
Techopedia explains Refresh Rate
Refresh rate is a common figure used to gauge a computer monitor's or device screen's ability to effectively display the graphical and textual display output. It can be controlled using a compatible video/display card.
The refresh rate of a typical computer monitor ranges from 60 to 100 hertz depending on its screen size, whereas for an LCD monitor, refresh rate is on the higher side due to their advanced technology. Refresh rates lower than 70 hertz are considered negative rates as they cause the display screen to flicker.