A directive to perform the indicated note or chord of a composition with particular emphasis. The note or chord would be performed as if it had an accent as shown below and performed at the dynamic level indicated. It is typically shown as the abbreviation, sf, sff, or sfff.
This term can be confused with sforzato which has a similar effect (shown below) and is indicated by the abbreviation sfz, sffz, or sfffz. In fact, many music dictionaries show both sforzando and sforzato as having the same meaning.