alliteration
Repetition of the initial sounds of words: "dapple-dawn-drawn Falcon."

apostrophe
Language addressed to a person, animal, object, or other entity that is not present. See Talk to Animals (and Stars)
.

assonance
Repetition of vowel sounds: "d
apple-dawn-drawn Falcon."

blank verse
Lines of unrhymed iambic pentameter:

                         And I have felt
A presence that disturbs me with the joy

Of elevated thoughts; a sense sublime
Of something far more deeply interfused,
Whose dwelling is the light of setting suns,
And the round ocean and the living air,
And the blue sky, and in the mind of man;
A motion and a spirit, that impels                             100
All thinking things, all objects of all thought,
And rolls through all things.

Lines 93-102 from "Tintern Abbey" by William Wordsworth.

caesura
A significant pause within a line, often indicated with punctuation:

All nature is but art, unknown to thee;
All chance, direction, which thou canst not see . . .

Lines 289-290 from "An Essay on Man" by Alexander Pope.

consonance
Repetition of consonant sounds: "bare
ruined choirs."

enjambed line
A line of poetry that is run on to the following line without any pause:

Then, sometimes, in that silence, while he hung
Listening, a gentle shock of mild surprise
Has carried far into his heart the voice
Of mountain-torrents; or the visible scene
Would enter unawares into his mind
With all its solemn imagery . . .

Lines 18-23 from "There Was a Boy" by William Wordsworth.

end-stopped line
A line of poetry that ends with a full stop, usually with a punctuation mark:

All nature is but art, unknown to thee;
All chance, direction, which thou canst not see;
All discord, harmony, not understood;
All partial evil, universal good . . .

Lines 289-292 from "An Essay on Man" by Alexander Pope.

figurative language
Language that is used to imply or suggest a literal meaning, often by way of comparison. sometimes called figures of speech.

foot
A unit of stressed and unstressed syllables, used to establish a  meter.

Some common types of foot:
spondaic
iambic
anapestic
trochaic
dactylic

free verse
Poetry that does not use traditional meter or rhyme.

image
Use of vivid sensory language, often evoking abstract thoughts and feelings by association with concrete particulars.

literal meaning
The normal, ordinary, factual, unadorned meaning — without figurative associations.

metaphor
A figure of speech that associates one term with another. If we say, "Time is a river," we're noting a correspondence between the two.A metaphor has two parts: a tenor and a vehicle. The tenor ("time") is the literal subject of the metaphor, and the vehicle ("river") is a figurative reference to which the literal subject is implicitly being compared. See Follow a Metaphor.

meter
A regular tempo established by recurring numbers of feet within a line. Some common patterns are dimeter, two feet per line; trimeter, three feet per line; tetrameter, four feet per line; pentameter, five feet per line; hexameter, six feet per line.  Thus, a line with four trochaic feet is called trochaic tetrameter. A line with five iambic feet is iambic pentameter.

rhythm
The overall pacing and tempo of a poem as it is read. The poem's meter plays a role, but other factors such as sentence structure and emotional intensity also influence rhythm.

rhyme
Repetition of both vowel and consonant sounds: "dapple-dawn-drawn Falcon."

scan
To mark the meter of a poem by identifying patterns of stressed and unstressed syllables.

simile
A figure of speech that makes an explicit comparison. If we say, "Time is like a river," we're noting a correspondence, as in a metaphor, with the crucial difference that the comparison of a simile is made explicit, by use of the word "like," or in some cases the word "as."

stanza
A grouping of lines within a poem. A group of two lines is called a couplet. A three line stanza is called a tercet. A four line stanza is a quatrain, and a five line stanza is a quintet. Two other common lengths are a sestet, six lines; and an octave, eight lines.

sonnet
A traditional poetic form comprised of fourteen lines of iambic pentameter.  See Robert Frost's "Design"  for an example of an Italian sonnet and William Shakespeare's "Sonnet 73"  for an example of an English sonnet.

synecdoche
A type of figurative language which uses a part to refer to a whole, for example, using "wheels" for "car," as in, "I need some new wheels."

verse paragraph
Line groups of irregular length, which function much like paragraphs in prose.

villanelle
A nineteen line poem with five three line stanzas and one concluding four line stanza. The stanzas feature an intricate pattern of repetition, as illustrated in Theodore Roethke's "The Waking" and Dylan Thomas's "Do Not Go Gentle Into That Good Night."