A star, such as the sun, having relatively low mass, small size, and average or below average luminosity.
A relatively small, low-mass star that emits an average or below-average amount of light. Most dwarf stars, including the Sun, are main-sequence stars, the principal exception being white dwarfs, which are the remnants of larger collapsed stars. Main-sequence dwarfs burn their hydrogen at a much slower rate than giant and supergiant stars and are consequently less luminous and have longer lifespans than those non-main-sequence stars do.
(astronomy) A star that is located in the main sequence in the Hertzsprung-Russell diagram; fuses hydrogen into helium in its core.