The most common and most likely answer to this crossword clue is the 10 letter word MASQUERADE
I've seen this crossword clue in Financial Times
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More clues leading to the result MASQUERADE
- Pretence created, as doubt briefly concealed
- Deception accomplished as short reservation's accepted
- Prepared to host special Question Time where everyone’s wearing the veil
- Costume ball designed to incorporate square dancing
- Pretence created to trap dinosaur, half taken aback
- Spy boss expressed hesitation infiltrating a military group by Eastern Front
- Kind of ball fashioned around square, oddly
- Ball made square amazingly
- What Spanish viewed in strange dream as deception
- Festival where everyone covers The Faces?
Buddy explains!

The straight part
We know that "disguise" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case disguise = masquerade.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 MASQUERADE mean?
MASQUERADE noun- An assembly or party of people wearing (usually elaborate or fanciful) masks and costumes, and amusing themselves with dancing, conversation, or other diversions.
- The act of wearing a mask or dressing up in a costume for, or as if for, a masquerade ball.
- An act of living under false pretenses; a concealment of something by a false or unreal show; a disguise, a pretence; also, a pretentious display.
- An assembly of varied, often fanciful, things.
- A cosplay event at which costumed attendees perform skits.
- A dramatic performance by actors in masks; a mask or masque.
- A Spanish entertainment or military exercise in which squadrons of horses charge at each other, the riders fighting with bucklers and canes.
- To take part in a masquerade; to assemble in masks and costumes; to wear a disguise.
- To pass off as a different person or a person with qualities that one does not possess; also, to make a pretentious show of being what one is not.
- To conceal (someone) with, or as if with, a mask; to disguise.