资料来源 : Webster's Revised Unabridged Dictionary (1913)

Pitch \Pitch\, v. t. [imp. & p. p. {Pitched}; p. pr. & vb. n.
   {Pitching}.] [See {Pitch}, n.]
   1. To cover over or smear with pitch. --Gen. vi. 14.

   2. Fig.: To darken; to blacken; to obscure.

            The welkin pitched with sullen could. --Addison.

资料来源 : WordNet®

pitched
     adj 1: (of sound) set to a certain pitch or key; usually used as a
            combining form; "high-pitched"
     2: set at a slant; "a pitched rather than a flat roof"