The Collaborative International Dictionary of English v.0.48:

Shearn \Shearn\, n. [AS. scearn. Cf. Scarn.]
   Dung; excrement. [Obs.] [Written also shern.] --Holland.
   [1913 Webster]

The Collaborative International Dictionary of English v.0.48:

Shern \Shern\, n.
   See Shearn. [Obs.]
   [1913 Webster]