Definition of "alcove"

alcove

/ˈæl.kəʊv/

noun
plural alcoves
1. (architecture) A small recessed area set off from a larger room.
  Quotations
  It was very different from such bookstores as he had been accustomed to patronize. Two stories of the old house had been thrown into one: the lower space was divided into little alcoves; above, a gallery ran round the wall, which carried books to the ceiling.
  1919, Christopher Morley, The Haunted Bookshop‎, New York, N.Y.: Grosset & Dunlap Publishers, page 4
2. A shady retreat.
3. (countable) The geographical and geological term for a steep-sided hollow in the side of an exposed rock face or cliff of a homogeneous rock type, that was water eroded.