The Collaborative International Dictionary of English v.0.48:

Ceil \Ceil\ (s[=e]l), v. t. [imp. & p. p. Ceiled (s[=e]ld); p.
   pr. & vb. n. Ceiling.] [From an older noun, fr. F. ciel
   heaven, canopy, fr. L. caelum heaven, vault, arch, covering;
   cf. Gr. koi^los hollow.]
   1. To overlay or cover the inner side of the roof of; to
      furnish with a ceiling; as, to ceil a room.
      [1913 Webster]

            The greater house he ceiled with fir tree. --2
                                                  Chron. iii. 5
      [1913 Webster]

   2. To line or finish a surface, as of a wall, with plaster,
      stucco, thin boards, or the like.
      [1913 Webster]

The Collaborative International Dictionary of English v.0.48:

Ceiling \Ceil"ing\, n. [See Cell, v. t.]
   1. (Arch.)
      (a) The inside lining of a room overhead; the under side
          of the floor above; the upper surface opposite to the
          floor.
      (b) The lining or finishing of any wall or other surface,
          with plaster, thin boards, etc.; also, the work when
          done.
          [1913 Webster]

   2. (Naut.) The inner planking of a vessel.
      [1913 Webster]

   Camp ceiling. See under Camp.

   Ceiling boards, Thin narrow boards used to ceil with.
      [1913 Webster]

WordNet (r) 3.0 (2006):

ceiling
    n 1: the overhead upper surface of a covered space; "he hated
         painting the ceiling"
    2: (meteorology) altitude of the lowest layer of clouds
    3: an upper limit on what is allowed; "he put a ceiling on the
       number of women who worked for him"; "there was a roof on
       salaries"; "they established a cap for prices" [syn:
       ceiling, roof, cap]
    4: maximum altitude at which a plane can fly (under specified
       conditions)

Moby Thesaurus II by Grady Ward, 1.0:

182 Moby Thesaurus words for "ceiling":
   CAT, acme, aerospace, aerosphere, air hole, air pocket, airspace,
   all, altitude, altitude peak, apogee, atmospheric visibility,
   automatic control, blast-off, border line, bottom price, bound,
   boundary, boundary condition, boundary line, bourn, break boundary,
   breakoff point, bump, burn, burnout, business index, ceiling price,
   ceiling unlimited, circumscription, clarity, clearness, climax,
   compass, confine, conspicuity, conspicuousness,
   consumer price index, cost-of-living index, crosswind, crown,
   crystal-clearness, cutoff, cutoff point, deadline, definiteness,
   definition, delimitation, demand curve, descent, determinant,
   distinctness, division line, eaves, elevation, eminence,
   empty space, end, end of burning, evidence, evidentness,
   exaltation, extreme, extremity, favorable wind, finish, flight,
   floor, floor price, fog, front, frontier, hauteur, head wind,
   hedge, height, heighth, high visibility, high-pressure area,
   high-water mark, highest degree, highness, hole, housetop,
   ignition, impact, inflation, inflationary spiral, interface,
   ionosphere, jetstream, lantern, launch, lift-off, limen, limit,
   limitation, limiting factor, line, line of demarcation, loftiness,
   low visibility, low-pressure area, low-water mark, lower limit,
   manifestness, march, mark, maximum, mete, ne plus ultra,
   nth degree, obviousness, overcast, overhead, patentness, peak,
   penthouse, percipi, perpendicular distance, pinnacle, plafond,
   plainness, pocket, price ceiling, price index, price level,
   prominence, ridgepole, rising prices, rocket launching, roof,
   roof garden, roof-deck, roofage, roofing, roofpole, rooftop,
   rooftree, roughness, seeing, shingles, shoot, shot, skylight,
   slates, soup, space, start, starting line, starting point, stature,
   stratosphere, sublimity, substratosphere, summit, tail wind,
   tallness, target date, term, terminal date, terminus, the whole,
   threshold, tiles, time allotment, top, top price, toploftiness,
   trajectory, tropopause, troposphere, trough, turbulence,
   upper limit, utmost, utmost extent, uttermost, velocity peak,
   visibility, visibility unlimited, visibility zero



Easton's 1897 Bible Dictionary:

Ceiling
   the covering (1 Kings 7:3,7) of the inside roof and walls of a
   house with planks of wood (2 Chr. 3:5; Jer. 22:14). Ceilings
   were sometimes adorned with various ornaments in stucco, gold,
   silver, gems, and ivory. The ceilings of the temple and of
   Solomon's palace are described 1 Kings 6:9, 15; 7:3; 2 Chr.
   3:5,9.