The most common and most likely answer to this crossword clue is the 7 letter word BYRONIC
B
Y
R
O
N
I
C
More clues leading to the result BYRONIC
- Writer embracing year performing as poet
- Cowshed shelved, both unfinished and romantically moody
- Gloomily romantic farm building mostly in readiness, but lacking final touch
- Corbyn: “I struggle to be broodingly handsome”
- Darkly romantic start of book by this writer breaking into corny frolicking
- Broodingly romantic and persistent, by ousting companion
- Like a Romantic poet of an earlier age — strange irony in that
- Romantically dark, cruel irony in ancient times
- Cynical Independent involved in Corbyn’s downfall
- Alluringly moody, wry leader getting ousted by Times
Buddy explains!

The straight part
We know that "Cynical" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case cynical = byronic.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.