User:SOTO/Forum Archive/The Panopticon/@comment-4028641-20151101035254/@comment-5918438-20160106171728
From Tardis Wiki, the free Doctor Who reference
T:DAB and T:CHAR NAMES state that we give character articles a disambiguation term based on the first story they appeared in. Plenty of those dabbed characters appeared in later stories as well, and perhaps their first story is not that which they're best known for. But it's still their first story, and the first story is what goes in the title.
Again, Osgood is not a primary topic like Elizabeth, the Doctor, regeneration or TARDIS. Other Osgoods are not all derived from her. She shares a common name with other people, so she gets dabbed.