'Penknife' definitions:

Definition of 'penknife'

From: WordNet
noun
A small pocketknife; originally used to cut quill pens

Definition of 'Penknife'

From: GCIDE
  • Penknife \Pen"knife`\, n.; pl. Penknives. [Pen + knife.] A small pocketknife; formerly, a knife used for making and mending quill pens. [1913 Webster]