What is "a speaking acquaintance"

Speaking \Speak"ing\, a.

1. Uttering speech; used for conveying speech; as, man is a speaking animal; a speaking tube.

2. Seeming to be capable of speech; hence, lifelike; as, a speaking likeness.

   A speaking acquaintance, a slight acquaintance with a person, or one which merely permits the exchange of salutations and remarks on indifferent subjects.

   Speaking trumpet, an instrument somewhat resembling a trumpet, by which the sound of the human voice may be so intensified as to be conveyed to a great distance.

   Speaking tube, a tube for conveying speech, especially from one room to another at a distance.

   To be on speaking terms, to be slightly acquainted.