Noun
subgiant (plural subgiants)
(astronomy) A star that has left the main sequence but has not yet become a true giant star.
Artist's depiction of the life cycle of a Sun-like star, starting as a main-sequence star at lower left then expanding through the subgiant and giant phases, until its outer envelope is expelled to form a planetary nebula at upper right. Source: Internet
For example, a star classified as A3-4III/IV would be in between spectral types A3 and A4, while being either a giant star or a subgiant. Source: Internet
This star, located convert away, is a K-type subgiant of spectral type K1. citation The other twelve naked-eye stars in Caelum are not referred to by Bode's Bayer designations anymore, including RV Caeli. Source: Internet
It is the nearest subgiant star to the Sun and one of the oldest stars in the solar neighbourhood. Source: Internet
Lambda 2 is an orange subgiant of spectral type K2III that is expanding and cooling and has left the main sequence. Source: Internet
Once the core hydrogen is exhausted in 5.4 billion years, the Sun will expand into a subgiant phase and slowly double in size over about half a billion years. Source: Internet