The most common and most likely answer to this crossword clue is the 5 plus 6 letter word RIGHT WINGER
I've seen this crossword clue in The Daily Telegraph
R
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G
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W
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More clues leading to the result RIGHT WINGER
Buddy explains!
The straight part
We know that "Ultra-Conservative" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case ultra-conservative = right winger.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 RIGHT WINGER mean?
RIGHT WINGER noun- A person who belongs to the political right.
- A member of the right wing of a party or group.
- A winger who plays on the right.