Luminosity refers to the brightness or radiance of something, like a light bulb or a star. It measures the amount of light it emits, with higher luminosity meaning it is brighter. Full definition
Hugely charismatic, humble, and possessed of preternatural luminosity of spirit, Wangari Maathai, the winner of the 2004 Nobel Peace Prize and a single mother of three, recounts her extraordinary life as a political activist, feminist, and environmentalist in Kenya. (bookbrowse.com)
CD - 23 17699 is a orange - red dwarf star of uncertain spectral type K5 to M0 (NStars), but there seems to be agreement that it is a main - sequence dwarf of luminosity type of V. (solstation.com)
Such stars are rich in carbon, and it is believed that the fall in brightness is due to the star's emission of carbon, which then condenses to a dense cloud near the star, rather than to a change in luminosity of the star itself. (britannica.com)