What Is an Iamb in Poetry?

Have you heard a poet or English teacher talk about iambic meter? It's a reference to the rhythm of a poem. Once you learn what it is, you will be able to recognize it in poetry and use it when writing your own verse.

What Is an Iamb?

An iamb (pronounced EYE-am) is a type of metrical foot in poetry. A foot is the unit of stressed and unstressed syllables that determines what we call the meter, or rhythmic measure, in the lines of a poem.

An iambic foot consists of two syllables, the first unstressed and the second stressed so that it sounds like “da-DUM.” One iambic foot can be a single word or a combination of two words:

• "away" is one foot: "a" is unstressed, and "way" is stressed
• "the crow" is one foot: "the" is unstressed, and "crow" is stressed

A perfect example of iambs is found in the last two lines from Shakespeare’s Sonnet 18:

So LONG / as MEN / can BREATHE / or EYES / can SEE,
So LONG / lives THIS,/ and THIS / gives LIFE / to THEE.

These lines from Shakespeare's sonnet are in iambic pentameter. Iambic meter also is defined by the number of iambs per line, in this case, five.

5 Common Types of Iambic Meter

Iambic pentameter might be the most recognizable type of iambic meter, as many famous poems use it. Iambs are all about pattern and rhythm, and you will quickly notice a pattern to the types of iambic meters:

• iambic dimeter: two iambs per line
• iambic trimeter: three iambs per line
• iambic tetrameter: four iambs per line
• iambic pentameter: five iambs per line
• iambic hexameter: six iambs per line

Examples: Robert Frost's "Dust of Snow" and "The Road Not Taken" are popular in iambic studies.

A Little Iambic History

The term "iamb" originated in classical Greek prosody as “iambos,” referring to a short syllable followed by a long syllable. The Latin word is "iambus." Greek poetry was measured in quantitative meter, determined by the length of the word-sounds, while English poetry, from the time of Chaucer through the 19th century, has been dominated by accentual-syllabic verse, which is measured by the stress or accent given to syllables when a line is spoken.

Both forms of verse use the iambic meter. The biggest difference is that the Greeks concentrated not just on how the syllables sounded, but their actual length.

Traditionally, sonnets are written in iambic pentameter with a strict rhyming structure. You will also notice it in many of Shakespeare's plays, particularly when a higher-class character speaks. 

A style of poetry known as blank verse also uses iambic pentameter, yet in this case, rhyming is not required or encouraged. You can find this in the works of Shakespeare as well as those of Robert Frost, John Keats, Christopher Marlowe, John Milton, and Phillis Wheatley.