All terms in this list:

Alliteration: The repetition of consonants at the beginning of two or more words immediately succeeding each other, or at short intervals; as in the following lines: -

allusion: An indirect reference; a hint; a reference to something supposed to be known, but not explicitly mentioned; a covert indication.

assonance: The repetition of similar or identical vowel sounds (though with different consonants), usually in literature or poetry.

ballad: A long song or poem that tells a story.

consonance: The repetition of consonant sounds, but not vowels as in assonance.

diction: The effectiveness and degree of clarity of word choice, and presentation of said words.

enjambment: A technique in poetry whereby a sentence is carried over to the next line without pause.

free verse: A poetic form divided into lines of no particular length or meter, without a rhyme scheme.

metaphor: (rhetoric) The use of a word or phrase to refer to something that it isn’t, invoking a direct similarity between the word or phrase used and the thing described, but in the case of English without the words like or as, which would imply a simile.

meter: The measured arrangement of sounds/beats in a poem, including the poet's placement of emphasis and the number of syllables per line.

Onomatopoeia: The property of a word of sounding like what it represents.

rhythm: The variation of strong and weak elements (such as duration, accent) of sounds, notably in speech or music, over time; a beat or meter.

simile: A figure of speech in which one thing is compared to another, in the case of English generally using like or as.

stanza: A unit of a poem, written or printed as a paragraph; equivalent to a verse.

symbol: Any object, typically material, which is meant to represent another (usually abstract) even if there is no meaningful relationship.

theme: the central meaning or dominate message the poet is trying to deliver to the reader.

tone: A specific pitch.

verse: A poetic form with regular meter and a fixed rhyme scheme.