Ripieno
The tutti string group in the concerto grosso.
What it means
Ripieno (Italian for "filled, full") denotes, in the Baroque concerto grosso, the larger string group with several players per part, as opposed to the small group of soloists, the concertino.
Musical use
In a typical concerto grosso, sections played by the concertino, scored for one to four soloists, alternate with tutti sections played by the ripieno, which brings in the full ensemble to confirm or develop the themes. The ripieno is distinct from the term tutti: tutti describes any fully-scored passage in a work generally, while ripieno specifically names the accompanying group in a concerto grosso, which exists as a group even when it is silent.
Performance practice
When performing a concerto grosso, aim for a clear contrast in sound: the ripieno should sound fuller and more powerful in its tutti entries than the more delicate concertino, so that the Baroque alternation of sound masses is clearly audible.