GNU Collaborative International Dictionary of English

Found one definition

1.       
   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.
   
   [1913 Webster]
   
   
   2. Fig.: To darken; to blacken; to obscure.
   
   [1913 Webster]
   
   The welkin pitched with sullen could. Addison.
   
   [1913 Webster]