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.
A vocal performance with no instrumental accompaniment.
Sole; being the only one of a type.
Situated by itself or by oneself, with no neighbours.
Solitary; having no companion.
Isolated or lonely; lacking companionship.