The most common and most likely answer to this crossword clue is the 8 letter word QUATRAIN
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More clues leading to the result QUATRAIN
- Short poem, as exercise
- Poet may write it as exercise
- Verse, one of five impressing a West End academician
- One in five children retaining a largely traditional verse
- Daughter bypasses courtyard to teach some poetry
- On courtyard, briefly teach part of poem
- As a vehicle for verse
- A set of lines as form of transport
- Verse from Iraq aunt translated
- Question a tutor producing four lines of verse
Buddy explains!

The straight part
We know that "A set of lines" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case a set of lines = quatrain.The cryptic/wordplay part
In cryptic crossword there's often an wordplay/cryptic part as well.This part involves a more complex hint, such as an anagram, homophone, hidden word, etc.
Sadly, We don't have an explanation for this specific crossword clue yet.
What does QUATRAIN mean?
QUATRAIN noun- A poem in four lines.
- A stanza of four lines.