In Aliens, the synthetic human who serves with the colonial Marines is named Bishop.
Bishop is the artificial person assigned to the Sulaco’s expedition, where he serves as the unit’s executive officer and science-oriented synthetic. Unlike Ash in Alien, Bishop is presented as generally trustworthy, although Ripley remains understandably wary because of the earlier film’s betrayal.
Lance Henriksen plays Bishop. The film uses his character to explore changing attitudes toward androids: Bishop is capable of remarkable physical feats, including navigating a dangerous gap between vehicles, yet he is also constrained by company protocols and artificial biology.
Bishop is often confused with other synthetic characters in the Alien series. Ash is the android in Alien, while David and Walter are synthetic beings played by Michael Fassbender in the prequel films Prometheus and Alien: Covenant. Bishop is specifically the synthetic in Aliens.