familiar

a.

  1. Of or pertaining to a family; domestic.
  2. Closely acquainted or intimate, as a friend or companion; well versed in, as any subject of study; as, familiar with the Scriptures.
  3. Characterized by, or exhibiting, the manner of an intimate friend; not formal; unconstrained; easy; accessible.
  4. Well known; well understood; common; frequent; as, a familiar illustration.
  5. Improperly acquainted; wrongly intimate.

n.

  1. An intimate; a companion.
  2. An attendant demon or evil spirit.
  3. A confidential officer employed in the service of the tribunal, especially in apprehending and imprisoning the accused.