Hagdon \Hag"don\ (h[a^]g"d[o^]n), n. (Zool.) One of several species of sea birds of the genus Puffinus; esp., Puffinus major, the greater shearwarter, and Puffinus Stricklandi, the black hagdon or sooty shearwater; -- called also hagdown, haglin, and hag. See Shearwater. [1913 Webster]

Source: The Collaborative International Dictionary of English v.0.48