College sentimentality that's mythical (7)

I believe the answer is:

unicorn

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'that's mythical' is the definition.
I can't tell whether this defines the answer.

'college sentimentality' is the wordplay.
'college' becomes 'uni' (short for university).
'sentimentality' becomes 'corn' (corniness).
'uni'+'corn'='UNICORN'

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(Other definitions for unicorn that I've seen before include "Mythical white equine" , "Heraldic creature" , "Animal rumoured" , "Fabulous horned animal" , "Lion's traditional adversary" .)

I've seen this clue in The Daily Express.

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