General Terms:
* Verse: This is the most general term for a line or group of lines in a poem.
* Stanza: A group of lines forming a unit in a poem, often separated by a space.
* Couplet: Two lines that rhyme and usually form a complete thought.
Specific Forms:
* Quatrain: A four-line stanza.
* Sestet: A six-line stanza.
* Octave: An eight-line stanza.
* Tercet: A three-line stanza.
Other Terms:
* Line: A single line of poetry.
* Refrain: A line or group of lines that is repeated throughout a poem.
* Chorus: A refrain in a song.
Example:
In a sonnet, the first eight lines form an octave, and the last six lines form a sestet. Each line is a verse and each group of four lines is a quatrain.
Important Note: The specific terminology used for a poem's verse depends on the poem's form and the poet's choices.