Crossword Genius

Bombast, that - unctuous at first, unusually rigid, extremely tacky (9)

Ross

I believe the answer is:

turgidity

'bombast' is the definition.
(thesaurus)

'that unctuous at first unusually rigid extremely tacky' is the wordplay.
'at first' says to take the initial letters.
'unusually' indicates anagramming the letters.
'extremely' says to hollow out the word (remove centre letters).
'tacky' with its centre removed is 'ty'.
The first letters of 'that unctuous' is 'tu'.
'rigid' with letters rearranged gives 'rgidi'.
'tu'+'rgidi'+'ty'='TURGIDITY'

I've seen this clue in The Independent.
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