My best guess is this is Liu Tanzhi 劉坦之. He is quoted in Ding Fubao's annotations, where he makes the connection to the term as used in Huainanzi. I don't know where Ding is getting Liu's comments, though, since I don't have the full Ding ed, only Wang Shumin's 王叔岷 陶淵明詩箋證稿, see screenshot