A directive to perform a specific 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, sfz, sffz, or sfffz.
This term can be confused with sforzando which has a similar effect (shown below) and is indicated by the abbreviation sf, sff, or sfff. In fact, many music dictionaries show both Sforzato and sforzando as having the same meaning.
Read more about dynamic markings in the Appendix.