A vocal performance with no instrumental accompaniment.
Singing solely or mainly without instrumental accompaniment.
Related to a form of purely vocal music mostly associated with American college performance groups.
In a manner of a choir with no instrumental accompaniment; literally, "in the style of the (Sistine) Chapel (in Rome)", such as a musical Mass done a cappella.
The murmuring sound made by a dove or pigeon.
An expression of pleasure made by a person.
To speak in an admiring fashion, to be enthusiastic about.
To make a soft murmuring sound, as a pigeon.
An expression of approval, fright, surprise, etc.
Cool.