What does "peen" mean?

Peen: (a) A round-edged, or hemispherical, end to the head of a hammer or sledge, used to stretch or bend metal by indentation. (b) The sharp-edged end of the head of a mason's hammer. [Spelt also pane, pein, and piend.]

Additional senses

  1. 2.To draw, bend, or straighten, as metal, by blows with the peen of a hammer or sledge.

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