Hill was short, like all her family, and indifferent to fashion. Her friend Henrietta Barnett wrote: "She was small in stature with a long body and short legs. She did not dress, she only wore clothes, which were often unnecessarily unbecoming; she had soft and abundant hair and regular features, but the beauty of her face lay in brown and very luminous eyes, which quite unconsciously she lifted upwards as she spoke on any matter for which she cared. Her mouth was large and mobile, but not improved by laughter. Indeed, Miss Octavia was nicest when she was made passionate by her earnestness." Barnett also spoke of Hill's streak of ruthlessness. Gertrude Bell called Hill despotic. Later in Hill's life, the Bishop of London, Frederick Temple, encountered her at a meeting of the Ecclesiastical Commissioners, and wrote, "She spoke for half an hour … I never had such a beating in all my life."