What does "pshaw" mean?

Pshaw: Pish! pooch! -- an exclamation used as an expression of contempt, disdain, dislike, etc. [Written also psha.]

Additional senses

  1. 2.To express disgust or contemptuous disapprobation, as by the exclamation " Pshaw!" The goodman used regularly to frown and pshaw wherever this topic was touched upon. Sir W. Scott.

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