What Is a Sonnet?

Shakespeare breathed life into this centuries-old poetic form

William Shakespeare Songs and Sonnets
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A sonnet is a one-stanza, 14-line poem, written in iambic pentameter. The sonnet, which derived from the Italian word sonetto, meaning “a little sound or song," is "a popular classical form that has compelled poets for centuries," says Poets.org. The most common—and simplest—type is known as the English or Shakespearean sonnet, but there are several other types.

Sonnet Characteristics

Before William Shakespeare’s day, the word sonnet could be applied to any short lyric poem.

In Renaissance Italy and then in Elizabethan England, the sonnet became a fixed poetic form, consisting of 14 lines, usually iambic pentameter in English.

Different types of sonnets evolved in the different languages of the poets writing them, with variations in rhyme scheme and metrical pattern. But all sonnets have a two-part thematic structure, containing a problem and solution, question and answer, or proposition and reinterpretation within their 14 lines and a volta, or turn, between the two parts.

Sonnets share these characteristics:

  • Fourteen lines: All sonnets have 14 lines, which can be broken down into four sections called quatrains.
  • A strict rhyme scheme: The rhyme scheme of a Shakespearean sonnet, for example, is ABAB / CDCD / EFEF / GG (note the four distinct sections in the rhyme scheme).
  • Written in iambic pentameter: Sonnets are written in iambic pentameter, a poetic meter with 10 beats per line made up of alternating unstressed and stressed syllables.

    A sonnet can be broken into four sections called quatrains. The first three quatrains contain four lines each and use an alternating rhyme scheme. The final quatrain consists of just two lines, which both rhyme. Each quatrain should progress the poem as follows:

    1. First quatrain: This should establish the subject of the sonnet.
        Number of lines: four; rhyme scheme: ABAB
    1. Second quatrain: This should develop the sonnet’s theme.
       Number of lines: four; rhyme scheme: CDCD
    2. Third quatrain: This should round off the sonnet’s theme.
        Number of lines: four; rhyme scheme: EFEF
    3. Fourth quatrain: This should act as a conclusion to the sonnet.
       Number of lines: two; rhyme scheme: GG

    Sonnet Form

    The original form of the sonnet was the Italian or Petrarchan sonnet, in which 14 lines are arranged in an octet (eight lines) rhyming ABBA ABBA and a sestet (six lines) rhyming either CDECDE or CDCDCD.

    The English or Shakespearean sonnet came later, and, as noted, is made of three quatrains rhyming ABAB CDCD EFEF and a closing rhymed heroic couplet, GG. The Spenserian sonnet is a variation developed by Edmund Spenser in which the quatrains are linked by their rhyme scheme: ABAB BCBC CDCD EE.

    Since its introduction into English in the 16th century, the 14-line sonnet form has remained relatively stable, proving itself a flexible container for all kinds of poetry, long enough that its images and symbols can carry detail rather than becoming cryptic or abstract, and short enough to require a distillation of poetic thought.

    For more extended poetic treatment of a single theme, some poets have written sonnet cycles, a series of sonnets on related issues often addressed to a single person.

    Another form is the sonnet crown, a sonnet series linked by repeating the last line of one sonnet in the first line of the next until the circle is closed by using the first line of the first sonnet as the last line of the last sonnet.

    The Shakespearean Sonnet

    The most well-known and important sonnets in the English language were written by Shakespeare. These sonnets cover such themes as love, jealousy, beauty, infidelity, the passage of time, and death. The first 126 sonnets are addressed to a young man while the last 28 are addressed to a woman.

    The sonnets are constructed with three quatrains (four-line stanzas) and one couplet (two lines) in the meter of iambic pentameter (like his plays). By the third couplet, the sonnets usually take a turn, and the poet comes to some kind of epiphany or teaches the reader a lesson of some sort.

    Of the 154 sonnets Shakespeare wrote, a few stand out.

    A Summer's Day

    Sonnet 18 is probably the most well known of all of Shakespeare's sonnets:

    "Shall I compare thee to a summer's day? 
    Thou art more lovely and more temperate:
    Rough winds do shake the darling buds of May,
    And summer's lease hath all too short a date: 
    Sometime too hot the eye of heaven shines,
    And often is his gold complexion dimm'd; 
    And every fair from fair sometime declines,
    By chance, or nature's changing course, untrimm'd;
    But thy eternal summer shall not fade
    Nor lose possession of that fair thou ow'st;
    Nor shall Death brag thou wander'st in his shade,
    When in eternal lines to time thou grow'st; 
    So long as men can breathe or eyes can see,
    So long lives this, and this gives life to thee."

    This sonnet best exemplifies the three-quatrain-and-one-couplet model, as well as the iambic pentameter meter. While many people assumed Shakespeare was addressing a woman, he is, in fact, addressing the Fair Youth.

    He compares the young man to the beauty of a summer's day, and just as the day and seasons change, so to do humans, and while the Fair Youth will eventually age and die, his beauty will be remembered forever in this sonnet.

    Dark Lady

    Sonnet 151 is about the Dark Lady, the object of the poet's desire, and is more overtly sexual:

    "Love is too young to know what conscience is; 
    Yet who knows not, conscience is born of love? 
    Then, gentle cheater, urge not my amiss, 
    Lest guilty of my faults thy sweet self prove. 
    For thou betraying me, I do betray 
    My nobler part to my gross body's treason; 
    My soul doth tell my body that he may 
    Triumph in love; flesh stays no farther reason, 
    But rising at thy name, doth point out thee 
    As his triumphant prize. Proud of this pride, 
    He is contented thy poor drudge to be, 
    To stand in thy affairs, fall by thy side. 
    No want of conscience hold it that I call 
    Her 'love,' for whose dear love I rise and fall."

    In this sonnet, Shakespeare first asks the Dark Lady to not admonish him for his sin, as she is also "sinning" with him and the Fair Youth. He then speaks to how he feels betrayed by his own body because he is merely following his base instincts, which have enslaved him to Dark Lady.