apprehender
1. [ noun ] a person who knows or apprehends
Synonyms: knower
Related terms: person apprehend
2. [ noun ] a person who seizes or arrests (especially a person who seizes or arrests in the name of justice)
Related terms: person collar
Similar spelling:   apprehend
  apprehended
  apprehensive
  apprehension
  apprehensible
  apprehanded
  apprehensively
  apprentice
  apprenticed