white dwarf

American  

noun

Astronomy.

1. a star, approximately the size of the earth, that has undergone gravitational collapse and is in the final stage of evolution for low-mass stars, beginning hot and white and ending cold and dark black dwarf.

---

white dwarf British  

noun

1. one of a large class of small faint stars of enormous density (on average 10 ⁸ kg/m³) with diameters only about 1 per cent that of the sun, and masses less than the Chandrasekhar limit (about 1.4 solar masses). It is thought to mark the final stage in the evolution of a sun-like star

---

white dwarf Scientific  

1. A small, extremely dense star characterized by high temperature and luminosity. A white dwarf is believed to be in its final stage of evolution, having either used up most of its nuclear fuel in its main-sequence stage, or else moved through a giant stage and shed any remaining fuel in its outer layer as a planetary nebula, leaving only a glowing core. Some 10 percent of all stars in the Milky Way are white dwarfs, but despite their intrinsic luminosity, they are so small that none are visible to the naked eye.

2. See Note at dwarf

---

white dwarf Cultural  

1. A kind of star about the size of the Earth. White dwarfs represent a final stage of the life cycle of stars similar to the sun; they are formed when the stars use up their fuel and can no longer support nuclear reactions.

---

Etymology

Origin of white dwarf

First recorded in 1920–25

Example Sentences

See Examples For:

white dwarf

The lion's mane corresponds to the inner region of a dust shell illuminated by the white dwarf at the center.

From Science Daily ● Aug. 12, 2026

Earlier research suggested that if one passed through a white dwarf, its gravity could create powerful tidal forces inside the star.

From Science Daily ● Aug. 1, 2026

An international research team has found that primordial black holes may trigger white dwarf stars to explode as Type Ia supernovae.

From Science Daily ● Aug. 1, 2026

Evidence for white dwarf kicks comes from research led by Kareem El-Badry, an assistant professor of astronomy at Caltech.

From Science Daily ● Jul. 21, 2026

But a more massive star will spend its nuclear fuel faster, become a red giant sooner, and be first to enter the final white dwarf decline.

From "Cosmos" by Carl Sagan