Familiar

1. Closely acquainted or intimate, as a friend or companion; well versed in, as any subject of study; as, familiar with the Scriptures.
2. An intimate; a companion.
3. A confidential officer employed in the service of the tribunal, especially in apprehending and imprisoning the accused.
4. An attendant demon or evil spirit.
5. Characterized by, or exhibiting, the manner of an intimate friend; not formal; unconstrained; easy; accessible.
6. Well known; well understood; common; frequent; as, a familiar illustration.
7. Improperly acquainted; wrongly intimate.