The Collaborative International Dictionary of English v.0.48:

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.
   [1913 Webster]

The Collaborative International Dictionary of English v.0.48:

Sollar \Sol"lar\, n.
   1. See Solar, n. [Obs.]
      [1913 Webster]

   2. (Mining) A platform in a shaft, especially one of those
      between the series of ladders in a shaft.
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The Collaborative International Dictionary of English v.0.48:

Sollar \Sol"lar\, v. t.
   To cover, or provide with, a sollar.
   [1913 Webster]