giant star

American  

noun

1. a star having a diameter of from 10 to 100 times that of the sun, as Arcturus or Aldebaran.

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giant star British  

noun

1. Sometimes shortened to: giant.  any of a class of stars, such as Capella and Arcturus, that have swelled and brightened considerably as they approach the end of their life, their energy supply having changed Compare supergiant

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giant star Scientific  

1. A very large, bright non-main-sequence star that burns hydrogen at a much faster rate than a dwarf star. Giant stars are much more luminous and have shorter lifespans than the slower-burning dwarfs. The larger the giant, the shorter its lifespan; the largest stars, with solar mass of around 100, blaze at several hundred thousand times the energy of the Sun and will last only a few million years, a very brief time when compared with the Sun's 10-billion-year lifespan. Giant stars usually end their lives as supernovae , but even before that event the immense ultraviolet radiation they produce has a dramatic impact on their stellar surroundings; the presence of a giant star in a star system prevents the formation of new protostars because the radiation from the giant star breaks apart any nearby nebulae.

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Etymology

Origin of giant star

First recorded in 1910–15

Example Sentences

That is the conclusion of a new study from Chalmers University of Technology in Sweden, based on close observations of the red giant star R Doradus.

From Science Daily • Jan. 12, 2026

The phenomenon occurs when a white dwarf and red giant star orbit each other.

From Los Angeles Times • May 22, 2024

The scientists have now found hidden stars, including a new type of elderly giant star nicknamed "an old smoker".

From BBC • Jan. 27, 2024

This blue giant star lies 97 light-years from Earth and shines 200 times brighter than our sun.

From National Geographic • Aug. 23, 2023

The Sun will become a red giant star, its visible surface so far from its interior that the gravity at its surface grows feeble, its atmosphere expanding into space in a kind of stellar gale.

From "Cosmos" by Carl Sagan