asymptotic giant branch (redirected from AGB Star)

asymptotic giant branch [‚a‚sim¦täd·ik ‚jī·ənt ′branch]

(astronomy)

A grouping of stars on the Hertzsprung-Russell diagram that is roughly asymptotic to the giant branch; it represents a later stage in giant-star evolution in which hydrogen-fusing and helium-fusing shells surround a core in which both hydrogen fusion and helium fusion are exhausted. Abbreviated AGB.