Source : Webster's Revised Unabridged Dictionary (1913)

Solar \So"lar\, n. [OE. soler, AS. solere, L. solarium, from sol
   the sun. See {Solar}, a.]
   A loft or upper chamber; a garret room. [Obs.] [Written also
   {soler}, {solere}, {sollar}.] --Oxf. Gloss.

Solar \So"lar\, a. [L. solaris, fr. sol the sun; akin to As.
   s[=o]l, Icel. s[=o]l, Goth. sauil, Lith. saule, W. haul,.
   sul, Skr. svar, perhaps to E. sun:F. solaire. Cf. {Parasol}.
   {Sun}.]
   1. Of or pertaining to the sun; proceeding from the sun; as,
      the solar system; solar light; solar rays; solar
      influence. See {Solar system}, below.

   2. (Astrol.) Born under the predominant influence of the sun.
      [Obs.]

            And proud beside, as solar people are. --Dryden.

   3. Measured by the progress or revolution of the sun in the
      ecliptic; as, the solar year.

   4. Produced by the action of the sun, or peculiarly affected
      by its influence.

            They denominate some herbs solar, and some lunar.
                                                  --Bacon.

   {Solar cycle}. See under {Cycle}.

   {Solar day}. See {Day}, 2.

   {Solar engine}, an engine in which the energy of solar heat
      is used to produce motion, as in evaporating water for a
      steam engine, or expanding air for an air engine.

   {Solar flowers} (Bot.), flowers which open and shut daily at
      certain hours.

   {Solar lamp}, an argand lamp.

   {Solar microscope}, a microscope consisting essentially,
      first, of a mirror for reflecting a beam of sunlight
      through the tube, which sometimes is fixed in a window
      shutter; secondly, of a condenser, or large lens, for
      converging the beam upon the object; and, thirdly, of a
      small lens, or magnifier, for throwing an enlarged image
      of the object at its focus upon a screen in a dark room or
      in a darkened box.

Source : WordNet®

solar
     adj : relating to or derived from the sun or utilizing the
           energies of the sun; "solar eclipse"; "solar energy"