Plath wrote “Lady Lazarus” in free verse, which means the poem doesn’t have a rigid metrical scheme. Indeed, the meter is so consistently irregular that no single tercet in the entire poem has a perfectly straight rhythm. From line to line, and often even within a single line, the rhythm shifts between rising and falling meter. The term rising meter refers to any rhythmic scheme emphasizing metrical feet that start with an unstressed syllable and finish with a stressed syllable. Iambs (unstressed–stressed) and anapests (unstressed–unstressed–stressed) are both types of rising meter. By contrast, falling meter emphasizes metrical feet that start with a stressed syllable and finish with an unstressed syllable. Trochees (stressed–unstressed) and dactyls (stressed–unstressed–unstressed) are both types of falling meter. As its name indicates, rising meter creates a sensation of upward movement, almost as if the poetic line is building something up. Likewise, falling meter evokes a sensation of downward movement, as if the poetic line is collapsing.

To see how “Lady Lazarus” oscillates between rising and falling meter, consider the opening tercets (lines 1–6):

     I have | done it | a-gain.
(2 trochees + 1 iamb)
     One year | in ev- | ery ten
(1 trochee + 2 iambs)
     I man- | age it——
(2 iambs)

     A sort | of walk- | ing mir- | a-cle, | my skin
(5 iambs)
     Bright as a | Na-zi | lamp-shade,
(1 dactyl + 2 trochees)
     My right foot
(1 molossus)

Note how, in the first tercet, the meter shifts frequently between trochees and iambs. The first line begins with two trochees and ends with an iamb. The second line also begins with a trochee, but then reverts to iambs for the second and third feet. The two lines on either side of the stanza break both consist entirely of iambs, giving the brief impression of regular iambic rhythm. But that impression quickly dissipates in the rest of the second tercet, which includes the very unusual metrical foot known as a molossus, which has three stressed syllables. What results from all this oscillation between rising and falling meter is a sense of obstructed flow. If you read the poem aloud, you’ll find that you constantly need to slow down and speed up to account for all the sudden, minute rhythmic shifts. Considering the speaker’s unbalanced emotional state, we might interpret the metrical instability as echoing her mental instability. That is, the metrical rhythm rises and falls in parallel with the speaker’s emotional ups and downs.