Two rhyming lines (7)
I believe the answer is:
couplet
'two rhyming lines' is the definition.
(I've seen this before)
This is the entire clue.
(Other definitions for couplet that I've seen before include "Two successive lines of verse, usually rhyming" , "bit of poetry" , "piece of poetry" , "Pair of verse lines" , "Two lines of verse, often rhyming" .)