A tea room was a business that primarily served tea.
Ian Chesterton was vacationing in Dorset when he thought he saw his co-worker, Barbara Wright, sitting in a tea room with an older woman. (PROSE: The Splintered Gate)
The planet Jastan 7 had emerald tea rooms. (AUDIO: Voyage to Venus)
The Eleventh Doctor dreamt of enjoying an afternoon tea in a tea room, with scones, cream and jam, and in that dream was approached by a hooded figure, a messenger for Darla von Karlsen. (TV: Asylum of the Daleks Prequel)
Upon her death, Gretchen Carlisle arrived in a tea room in the Nethersphere. Missy, there, offered her tea. (TV: Into the Dalek)