Anacrusis


In poetic and musical meter, and by analogy in publishing, an anacrusis is a brief introduction. .
It is a set of syllables or notes, or a single syllable or note, which precedes what is considered the first foot of a poetic line in poetry and the first beat in music that is not its own phrase, section, or line and is not considered part of the line, phrase, or section which came before, if any.

Poetry

In poetry, a set of extrametrical syllables at the beginning of a verse is said to stand in anacrusis. "An extrametrical prelude to the verse," or, "extrametrical unstressed syllables preceding the initial lift."
The technique is seen in Old English poetry, and in lines of iambic pentameter, the technique applies a variation on the typical pentameter line causing it to appear at first glance as trochaic. The O! in the opening of "The Star-Spangled Banner" is an anacrusis in the anapestic tetrameter of the lyrics.

Music

In music, an anacrusis is a note or sequence of notes, a motif, which precedes the first downbeat in a bar in a musical phrase. "The span from the beginning of a group to the strongest beat in the group." Anacrusis, especially reoccurring anacrusis, "is a common means of weighting the first beat," and thus strengthening or articulating the meter.
The musical term is inferred from the terminology of poetry, where it refers to one or more first but unstressed syllables of a lyrical verse. Anacruses may involve fine details such as rhythm and phrasing, or may involve wider features such as musical form.
The anacrusis is a perceived grouping which is context generated in the individual phrasing of a concrete composition. The grouping of one or more antecedent tone events to a perceived phrase gestalt may be rhythmically evoked by their temporal proximity to the phrase's first downbeat.
An anacrusis may also be evoked solely metrically, i. e. tonally, that is, without the downbeat perception enforced by a relative long value.
Although the anacrusis is integrated in a musical phrase gestalt, it is not located in the perceived 'body' of the phrase, but before the phrase. In this respect -in a sequence of phrases- the anacrusis also may be perceived 'between' two phrases, neither being perceived as part of the ending of a former one, nor being located in the following one.
Outside of that the term of the anacrusis is most commonly used where it applies everywhere else 'within' the 'body' of the phrase between the 'head' and the 'foot' where, by what ever musical means, a grouping is perceived from an upbeat to a downbeat.
, begins on the upbeat and ends with a measure thus shortened.
Since an anacrusis "is an incomplete measure that allows the composition to start on a beat other than one," if anacrusis is present, the first bar after the anacrusis is assigned bar number 1, and Western standards for musical notation often include the recommendation that when a piece of music begins with an anacrusis, the notation should omit a corresponding number of beats from the final bar of the piece, or the final bar before a repeat sign, in order to keep the length of the entire piece at a whole number of bars. This final partial measure is the complement. However, an anacrusis may last an entire bar.

Examples

In academic publishing, the term is sometimes used in an article to mark an introductory idea standing between the abstract and the introduction proper.