What is the meaning of A_cappella?

A vocal performance with no instrumental accompaniment.

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.

In alla breve time.

Singing solely or mainly without instrumental accompaniment.

Related to a form of purely vocal music mostly associated with American college performance groups.

alla breve.

a cappella

a cappella

a cappella

a cappella

a cappella

a cappella

a cappella

a cappella (performed by a choir with no instrumental accompaniment)

a cappella (performed by a choir with no instrumental accompaniment)

Alternative form of à capela

Alternative spelling of a capela

a cappella

Source: wiktionary.org