The Collaborative International Dictionary of English v.0.48:

geography \ge*og"ra*phy\, n.; pl. Geographies. [F.
   g['e]ographie, l. geographia, fr. Gr. ?; ge`a, gh^, the earth
   + ? description, fr. ? to write, describe. See Graphic.]
   1. The science which treats of the world and its inhabitants;
      a description of the earth, or a portion of the earth,
      including its structure, features, products, political
      divisions, and the people by whom it is inhabited. It also
      includes the responses and adaptations of people to
      topography, climate, soil and vegetation
      [1913 Webster + WordNet 1.5]

   2. A treatise on this science.
      [1913 Webster]

   Astronomical, or Mathematical, geography treats of the
      earth as a planet, of its shape, its size, its lines of
      latitude and longitude, its zones, and the phenomena due
      to to the earth's diurnal and annual motions.

   Physical geography treats of the conformation of the
      earth's surface, of the distribution of land and water, of
      minerals, plants, animals, etc., and applies the
      principles of physics to the explanation of the
      diversities of climate, productions, etc.

   Political geography treats of the different countries into
      which earth is divided with regard to political and social
      and institutions and conditions.
      [1913 Webster]

The Collaborative International Dictionary of English v.0.48:

Astronomical \As`tro*nom"ic*al\ (-[i^]*kal), a. [L.
   astronomicus, Gr. 'astronomiko`s: cf. F. astronomique.]
   Of or pertaining to astronomy; in accordance with the methods
   or principles of astronomy. -- As`tro*nom"ic*al*ly, adv.
   [1913 Webster]

   Astronomical clock. See under Clock.

   Astronomical day. See under Day.

   Astronomical fractions, Astronomical numbers. See under
      Sexagesimal.
      [1913 Webster]

WordNet (r) 3.0 (2006):

astronomical
    adj 1: relating or belonging to the science of astronomy;
           "astronomic telescope" [syn: astronomic,
           astronomical]
    2: inconceivably large [syn: astronomic, astronomical,
       galactic]

Moby Thesaurus II by Grady Ward, 1.0:

98 Moby Thesaurus words for "astronomical":
   Atlantean, Brobdingnagian, Cyclopean, Cynthian, Gargantuan,
   Herculean, Homeric, abysmal, amplitudinous, anagalactic,
   asteroidal, astral, astrologic, astrologistic, astrologous,
   astronomic, astrophysical, awesome, boundless, bulky, celestial,
   circumplanetary, cislunar, colossal, cosmic, elephantine, empyreal,
   empyrean, enormous, epic, equinoctial, extensive, extragalactic,
   galactic, giant, giantlike, gigantic, heavenly, heliacal, heroic,
   huge, immeasurable, immense, infinite, intercosmic, interplanetary,
   intersidereal, interstellar, jumbo, king-size, large, lunar,
   lunary, lunate, lunular, lunulate, mammoth, massive, massy,
   meteoric, meteoritic, mighty, monster, monstrous, monumental,
   mountainous, nebular, nebulose, nebulous, outsize, overgrown,
   planetal, planetarian, planetary, planetesimal, prodigious,
   profound, semilunar, sidereal, sizable, solar, spacious, sphery,
   star-spangled, star-studded, starry, stellar, stellary, stupendous,
   terrestrial, titanic, towering, tremendous, uranic, vast,
   voluminous, weighty, zodiacal