The most common and most likely answer to this crossword clue is the 8 letter word FLUMMERY
I've seen this crossword clue in The Daily Telegraph
F
L
U
M
M
E
R
Y
More clues leading to the result FLUMMERY
Buddy explains!
The straight part
We know that "pretension" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case pretension = flummery.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 FLUMMERY mean?
FLUMMERY noun- A custard; any of several bland, gelatinous foodstuffs, usually made from stewed fruit and thickened with oatmeal, cornstarch or flour.
- Empty or meaningless talk, especially when used to flatter.
- Pretentious trappings, useless ornaments used to impress.
- Deceptive or blustering speech.
- An expression of contemptuous disbelief.