Ornament (music)

In music, ornaments or embellishments are musical flourishes—typically, added notes—that are not essential to carry the overall line of the melody, but serve instead to decorate or "ornament" that line, provide added interest and variety, and give the performer the opportunity to add expressiveness to a song or piece. Many ornaments are performed as "fast notes" around a central, main note.
There are many types of ornaments, ranging from the addition of a single, short grace note before a main note to the performance of a virtuosic and flamboyant trill. The amount of ornamentation in a piece of music can vary from quite extensive to relatively little or even none. The word agrément is used specifically to indicate the French Baroque style of ornamentation.

Improvised vs. written

In the Baroque period, it was common for performers to improvise ornamentation on a given melodic line. A singer performing a da capo aria, for instance, would sing the melody relatively unornamented the first time and decorate it with additional flourishes and trills the second time. Similarly, a harpsichord player performing a simple melodic line was expected to be able to improvise harmonically and stylistically appropriate trills, mordents and appoggiaturas.
Ornamentation may also be indicated by the composer. A number of standard ornaments are indicated with standard symbols in music notation, while other ornamentations may be appended to the score in small notes, or simply written out normally as fully sized notes. Frequently, a composer will have his or her own vocabulary of ornaments, which will be explained in a preface, much like a code. A grace note is a note written in smaller type, with or without a slash through it, to indicate that its note value does not count as part of the total time value of the bar. Alternatively, the term may refer more generally to any of the small notes used to mark some other ornament, or in association with some other ornament's indication, regardless of the timing used in the execution.
In Spain, melodies ornamented upon repetition were called "diferencias", and can be traced back to 1538, when Luis de Narváez published the first collection of such music for the vihuela.

Types

Trill

A trill, also known as a "shake", is a rapid alternation between an indicated note and the one above it. In simple music, trills may be diatonic, using just the notes of the scale; in other cases, the trill may be chromatic. The trill is usually indicated by either a or a, with the ~ representing the length of the trill, above the staff.
At a moderate tempo, the above might be executed as follows:
In Baroque music, the trill is sometimes indicated with a + sign above or below the note.
In the late 18th century, when performers played a trill, it always started from the upper note. However, "Heinrich Christoph Koch| Koch expressed no preference and observed that it was scarcely a matter of much importance whether the trill began one way or the other, since there was no audible difference after the initial note had been sounded." Clive Brown writes that "Despite three different ways of showing the trills, it seems likely that a trill beginning with the upper note and ending with a turn was envisaged in each case."
Sometimes it is expected that the trill will end with a turn, or some other variation. Such variations are often marked with a few grace notes following the note that bears the trill indication.
There is also a single tone trill variously called trillo or tremolo in late Renaissance and early Baroque. Trilling on a single note is particularly idiomatic for the bowed strings.

Mordent

A mordent is a rapid alternation between an indicated note, the note above or below, and the indicated note again. The upper mordent is indicated by a short thick tilde ; the lower mordent is the same with a short vertical line through it.
As with the trill, the exact speed with which a mordent is performed will vary according to the tempo of the piece, but, at a moderate tempo, the above might be executed as follows:
Confusion over the meaning of the unadorned word mordent has led to the modern terms upper and lower mordent being used, rather than mordent and inverted mordent. Practice, notation, and nomenclature vary widely for all of these ornaments; that is to say, whether, by including the symbol for a mordent in a musical score, a composer intended the direction of the additional note to be played above or below the principal note written on the sheet music varies according to when the piece was written, and in which country.
In the Baroque period, a mordant was what later came to be called an inverted mordent and what is now often called a lower mordent. In the 19th century, however, the name mordent was generally applied to what is now called the upper mordent. Although mordents are now thought of as a single alternation between notes, in the Baroque period a mordant may have sometimes been executed with more than one alternation between the indicated note and the note below, making it a sort of inverted trill. Mordents of all sorts might typically, in some periods, begin with an extra inessential note, rather than with the principal note as shown in the examples here. The same applies to trills, which in the Baroque and Classical periods would begin with the added, upper note. A lower inessential note may or may not be chromatically raised to make it one semitone lower than the principal note.

Turn

A turn is a short figure consisting of the note above the one indicated, the note itself, the note below the one indicated, and the note itself again. It is marked by a backwards S-shape lying on its side, sometimes known as an "inverted lazy S", above the staff. The details of its execution depend partly on the exact placement of the turn mark. For instance, the turns below
may be executed as
The exact speed with which a turn is executed can vary, as can its rhythm. The question of how a turn is best executed is largely one of context, convention, and taste. The lower and upper added notes may or may not be chromatically raised.
An inverted turn is usually indicated by putting a short vertical line through the normal turn sign, though sometimes the sign itself is turned upside down.

Appoggiatura

An appoggiatura is an added note that is important melodically and suspends the principal note by a portion of its time-value, often about half, but this may be considerably more or less depending on the context. The added note is one degree higher or lower than the principal note, and may or may not be chromatically altered. Appoggiaturas are also usually on the strong or strongest beat of the resolution, are themselves emphasised, and are approached by a leap and left by a step in the opposite direction of the leap.
An appoggiatura is often written as a grace note prefixed to a principal note and printed in small character, without the oblique stroke:
This may be executed as follows:

Acciaccatura

The word acciaccatura comes from the Italian verb acciaccare, "to crush". In the 18th century, it was an ornament applied to any of the main notes of arpeggiated chords, either a tone or semitone below the chord tone, struck simultaneously with it and then immediately released. Hence the German translation Zusammenschlag.
In the 19th century, the acciaccatura came to be a shorter variant of the long appoggiatura, where the delay of the principal note is quick. It is written using a grace note, with an oblique stroke through the stem. In the Classical period, an acciaccatura is usually performed before the beat and the emphasis is on the main note, not the grace note. The appoggiatura long or short has the emphasis on the grace note.
The exact interpretation of this will vary according to the tempo of the piece, but the following is possible:
Whether the note should be played before or on the beat is largely a question of taste and performance practice. Exceptionally, the acciaccatura may be notated in the bar preceding the note to which it is attached, showing that it is to be played before the beat. The implication also varies with the composer and the period. For example, Mozart's and Haydn's long appoggiaturas are – to the eye – indistinguishable from Mussorgsky's and Prokofiev's before-the-beat acciaccaturas.

Glissando

A glissando is a slide from one note to another, signified by a wavy line connecting the two notes.
All of the intervening diatonic or chromatic notes are heard, albeit very briefly. In this way, the glissando differs from portamento. In contemporary classical music, a glissando tends to assume the whole value of the initial note.

Slide

A slide instructs the performer to begin one or two diatonic steps below the marked note and slide upward. The schleifer usually includes a prall trill or mordent trill at the end. Willard A. Palmer writes that "he schleifer is a 'sliding' ornament, usually used to fill in the gap between a note and the previous one."

''Nachschlag''

The word Nachschlag translates, literally, to "after-beat", and refers to "the two notes that sometimes terminate a trill, and which, when taken in combination with the last two notes of the shake, may form a turn". The term Nachschlag may also refer to "an ornament that took the form of a supplementary note that, when placed after a main note, 'steals' time from it".
The first definition of Nachschlag refers to the "shaken" or trilled version of the ornament, while the second definition refers to the "smooth" version. This ornament has also been referred to as a cadent or a springer in English Baroque performance practice. Instruction books from the Baroque period, such as Christopher Simpson's The Division Violist, refer to the cadent as an ornament in which "a Note is sometimes graced by joyning part of its sound to the note following... whose following Quaver is Placed with the ensuing Note, but played with the same Bow."