An iambic pentameter is a specific type of a verse in lyric poetry that is built on iamb rhythmic patterns. Every line of a piece written in this style consists of 5 iambs, with a single iamb being a combination of 2 syllables – one unstressed and one stressed one.
In its traditional form, an iambic pattern can be shown in the following scheme:
× / × / × / × / × / – where "/" marks a stressed syllable and "x" stands for an unstressed syllable.
The term itself can be separated into two components. "Iamb" comes from Ancient Greek "iambos" and possibly derived from the name of a musical instrument that accompanied the performance of iambic songs. Another version of the origin of this term is that it derives from the name of the Greek goddess of verse – Iambe. "Pentameter" derives from two other words, with "penta" being translated as "five" and "meter" meaning the rhythmic organization of a verse.
It's critical to differentiate this style from other rhythmic patterns. A common mistake made by people is when they confuse an iambic pentameter with a trochaic pentameter. Both operate with disyllable metrical foots, but the latter has the first syllable stressed and followed by an unstressed one.
It's also important to distinguish different types of iambic lines. People unfamiliar with how meter systems work tend to miscount the number of iambs in a line and confuse a pentameter with a tetrameter or a hexameter.
One of the primary purposes of using an iambic pentameter is the same as with all rhythmical templates. This type of verse serves to add structure to a literary piece, underline the meaning of the words, and help increase its influence over the reader.
Authors like John Donne used to write in this style to add more elegance and smartness to their works. Shakespeare used iambic pentameters to put an emphasis on the intelligence of noble characters, as commoners in his plays all speak in prose.
In a lot of cases, this style also has a metaphorical reason behind its usage. For example, if a poet describes a stampede of wild animals rushing by the narrator, the rhythm can make it easier for the reader to imagine the sounds that surrounded the hero.
The traditional form of an iambic pentameter possesses an ear-pleasing structure and allows for building complex metaphors and images. However, since the 16th century, authors have noticed that if an entire literary work is written in this style, it gets stale and readers lose interest. As a result, poets began to add new details to the rhythmical patterns of this meter.
When a writer decides to skip a stressed syllable in one of the lines, that line is written in a pyrrhic meter. On the other hand, if a poet needs to put a couple of long syllables in a row, such a line becomes spondaic. An example of the latter case can be found in Shakespeare's "Richard III."
Another method that poets use to add variety to an iambic pentameter is to add a semi-stressed syllable instead of a fully stressed one. This is achieved by using longer words, and, as a result, long syllables are separated by three short ones.
The introduction of caesuras was another innovation that allowed authors to diversify their verses. A caesura is a literary tool that breaks a single line into two by using artificial pauses. Even though this technique and others destroy the initial rhythmical pattern of an iambic meter, the added variety makes a literary work more enjoyable for the reader.
Up until the end of the 18th century, the common understanding was that iambic verses were better suited for serious genres, while trochaic verses were best used for humorous purposes. Thus, prior to the 19th century, iambic pentameters were used to write elegies, tragedies, and other drama works. One of the earliest English-language works that were written in this verse style is the "Canterbury Tales" by Chaucer. It's important to note that sonnets were also usually written in this rhythmic pattern, which is especially evident in British and Russian works of literature. The sonnets of Shakespeare, for instance, were all written in this meter system.
However, as literature entered the 19th century, the use of iambic pentameter changed – there were no limitations anymore, and authors in all lyric poetry genres started to apply this meter system in their works quite actively. This style became one of the most popular rhythmical patterns in England, the United States, and Russia.
The iambic pentameter continued to be widely spread until the 20th century when modern, unstructured poems rose to prominence. However, this rhythmic pattern is still used to this day, mainly by poets who want to write a serious piece and strive to add more grandeur and better flow to their verses.