The most common and most likely answer to this crossword clue is the 7 letter word FANFARE
I've seen this crossword clue in The Daily Telegraph
F
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F
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More clues leading to the result FANFARE
- Stirring music from remote East introduced by devotee
- Real enthusiasts will swallow this ostentatious display
- Flourish provisions for keen supporters?
- Lover, go on and flourish
- Flourish; if cooler, manage
- Price of ticket needed by supporter for elaborate ceremony
- An enthusiast to get on and flourish
- Flourish to celebrate supporter’s travel cost
- Trump‘s half-time meat pie?
- With enthusiasm, display a half-time burger and pint?
Buddy explains!

The straight part
We know that "Ostentatious display" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case ostentatious display = fanfare.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 FANFARE mean?
FANFARE noun- A flourish of trumpets or horns as to announce; a short and lively air performed on hunting horns during the chase.
- A show of ceremony or celebration.
- To play a fanfare.
- To embellish with fanfares.
- To imitate a fanfare, in order to dramatize the presentation or introduction of something.
- To introduce with pomp and show.
- To mark an arrival or departure with music, noise, or drama.
- To publicize or announce.
- To fan out.