Sin:  Until.

Sinistra:  Left hand.

Sino:  Until.

Six-four chord:  The second inversion of a triad, made by placing the fifth of the chord in the lowest voice, e.g. Cis g-c-e.

Sixteenth note/rest:  A note/rest half the length of an eighth note and a sixteenth the length of a whole note.

Sixth:  The sixth degree of the diatonic scale. Also, the interval formed by a given tone and the sixth tone above or below it, e.g. c up to a, or c down to e. Intervals of the sixth may be major, minor, diminished, or augmented.

Sixth chord:  The first inversion of a triad, made by placing the third of the chord in the lowest voice, e.g. C6 is e-g-c.

Skip:  Melodic movement of more than one whole step.

Slur:  A curved line placed above or below two or more notes of different pitch to indicate that they are to be performed in legato style.

Smorzando:  Fading away.

Soave:  Sweet, mild.

Sognando:  Dreamily.

Sol:  In solmization, the fifth degree of the major scale.

Solmization:  The term for the use of syllables for the degrees of the major scale: do, re, mi, fa, sol, la ti, do. The minor scale (natural) is la, ti, do, re, mi, fa, sol, la.

Solo:  To perform alone or as the predominant part.

Sonata:  An instrumental piece, often in several movements.

Sonatina:  A short sonata.

Sostenuto:  Sustaining of tone or slackening of tempo.

Spiccato:  On string instruments, a bowing technique wherein the bow is bounced on the string at moderate speed.

Staccato:  Detached sounds, indicated by a dot over or under a note. The opposite of legato.

Staff:  The most frequently used staff has five horizontal lines, with four spaces, upon which the notes and other musical symbols are placed.

Stanza:  A selection of a song, two or more lines long, characterized by a common meter, rhyme, and number of lines.