In verse, a foot is the basic unit of meter used to describe rhythm. A foot consists of a certain number of syllables forming part of a line of verse. A foot is described by the character and number of syllables it contains: in English, feet are named for the combination of accented and unaccented syllables; in other languages such as Latin and Greek, the duration of the syllable (long or short) is measured.
When scanning a line of verse, a poet looks at feet as the basic rhythmic unit rather than words. A foot can consist of multiple words and a single word can contain many feet; furthermore, a foot can and often does bridge multiple words, containing, for example, the last two syllables of one word and the first of the next. To scan for feet, one should focus on the stream of sound alone and forget that words exist at all.
For example, here is the final couplet to a sonnet written in iambic pentameter by Edna St. Vincent Millay:
- Whether or not we find what we are seeking
- Is idle, biologically speaking.
In order to scan the poem (to break it into feet in order to analyze its meter), ignore word boundaries and break these lines down into stressed and unstressed syllables:
WHE ther or NOT we FIND what WE are SEE king IS ID le BI o LO gi CA ly SPEA king
The next step is to look at this stream of syllables and break it up into poetic feet. In English metered verse, a good rule of thumb is that there will be two or three syllables in each foot, one of which will be stressed. The entry for Meter (poetry) contains a useful list of kinds of poetic feet.
Here are the same lines now broken into feet:
WHE ther | or NOT | we FIND | what WE | are SEE king IS ID | le BI | o LO | gi CA | ly SPEA king
This example should make it clear that word boundaries have nothing to do with feet: "biologically" is part of four different feet in this poem!
Properly breaking a line down into syllables and feet requires some familiarity with the conventions of a particular meter and style. For example, because we know this is pentameter (lines with five feet), we have counted "biologically" as six syllables. In another poetic context, we might have easily written "bio LO gi ca ly."
Also realize that although these lines are written in iambic pentameter, not all of the feet are iambs (though the most common foot is an iamb). New students of verse often believe that lines in meter all have to follow the same pattern. Such students would either see these lines as free verse or force themselves to mispronounce the words ("whe-THER or NOT we FIND...") to fit the meter, producing a humorous effect which is not at all what the poet intended. On the contrary, scanning a line for feet that vary from the norm can help critics and poets understand the subtle changes in rhythm that create the unique effect of a given poem.