Alshain is Beta Aquilae, a yellow subgiant of spectral type G8 at about 45 light years, so relatively near that it is a modest star made noticeable only by its position. It lies just south of the brilliant Altair, with the orange giant Tarazed to the north, the three together forming the short line that makes the head of Aquila the eagle recognisable. The name comes, through Arabic, from a Persian word, shahin, the falcon, an older Persian name for the whole group of Altair and its two attendants as a bird, surviving here attached to the fainter of the flanking stars.
At only forty-five light years, Alshain is one of the nearer stars in this entire Andromeda-Aquila cluster of entries, close enough that its distance is known with real precision from direct trigonometric parallax rather than from the less certain spectroscopic methods needed for the more distant giants and supergiants that dominate the list. Being one of the nearer stars named in this whole cluster of Aquila entries, Alshain's true distance was pinned down by direct trigonometric parallax well before that of its more distant neighbours Tarazed and Altair's own galactic surroundings could be characterised in similar detail.
Sources AstronomyAndrew Fraknoi, David Morrison, and Sidney C. Wolff (OpenStax) with Star Names: Their Lore and MeaningRichard Hinckley Allen