Definition of "penthouse"

penthouse

/ˈpɛnt(h)aʊs/

noun
plural penthouses
1. (now historical) A structure or annexe (especially one with a sloping roof) extending from the side of a building, sometimes as protection from the weather.
  Quotations
  At length, recommending himself to God, he let go one end of his cord, and suffered himself to fall down upon an old shed or penthouse, which, with the weight of his body, fell in with great noise.
  1826, William Eusebius Andrews, Review of Fox's Book of Martyrs, WE Andrews, pages 386–7
2. (by extension, now rare) Something forming a shelter or canopy over something; an awning, shelter, etc.
  Quotations
  The proboscis […] is doubled up by means of the joint, and in that position lies secure under a scaly penthouse.
  1802, William Paley, Natural Theology, XIX
3. (tennis) Any of the sloping roofs at the side of a real tennis court.
  Quotations
  An odd derivative of real tennis lasted until the latter part of the eighteenth century at Rattray in Perthshire. It was played in the churchyard by two pairs of men, and the method for starting the play was to throw the ball onto the church roof, using it like the sloping penthouse of the tennis court.
  2005, Tony Collins (ed.), Encyclopaedia of Traditional British Rural Sports, Routledge, page 262
4. An apartment or suite found on an upper floor, or floors, of a tall building, especially one that is expensive or luxurious with panoramic views.
  Quotations
  Night of January 16th is the story of a woman on trial for pushing her wealthy boss-lover from a Manhattan penthouse.
  1995, Mary Ellen Waithe, Contemporary Women Philosophers: 1900-Today, Springer, page 214
verb
third-person singular simple present penthouses, present participle penthousing, simple past and past participle penthoused
1. (transitive) To provide with a penthouse, shelter by means of a shed sloping from a wall, or anything similar.