stellar

Stellar is an adjective meaning of, relating to, or resembling a star. The word is derived from the Latin stella, “star,” and entered English through late Latin and Old French in the early modern period.

In astronomy, stellar describes objects and phenomena associated with stars. Examples include stellar evolution, which traces a star’s life cycle from formation as a protostar to its endpoints as a white dwarf, neutron star, or black hole; stellar nucleosynthesis, the fusion processes that create heavier elements in stellar cores; and stellar atmospheres and spectra, which define a star’s light and classification. The spectral classification system (O, B, A, F, G, K, M) is used to describe stellar temperatures and properties. Other topics include stellar winds, stellar remnants, binaries, and the dynamics of star clusters and galaxies (stellar kinematics). Observational practice often uses parallax to measure stellar distances and proper motions to study their motions.

As a general English term, stellar is also used figuratively to mean outstanding or excellent. This sense is separate from the astronomical one and reflects the metaphor of stars as symbols of quality or prominence.