- (uncountable) A state of being acquainted, or of having intimate, or more than slight or superficial, knowledge; personal knowledge gained by intercourse short of that of friendship or intimacy
- I know of the man; but have no acquaintance with him.
- (countable) A person or persons with whom one is acquainted.
- 1848, Thomas Babington Macaulay, chapter XVI, in The History Of England From the Accession of James II:
- Montgomery was an old acquaintance of Ferguson.
- Synonym notes: The words acquaintance, familiarity, and intimacy mark different degrees of closeness in social intercourse. Acquaintance arises from occasional intercourse or interaction; as, "our acquaintance has been a brief one". We can speak of a slight or an intimate acquaintance. Familiarity is the result of continued acquaintance. It springs from persons being frequently together, so as to wear off all restraint and reserve; as, "the familiarity of old companions". Intimacy is the result of close connection, and the freest interchange of thought; as, "the intimacy of established friendship".
state of being acquainted